Java, Struts, Spring, & Hibernate

Event.stopPropagation() and Event.preventDefault()

noreply@blogger.com (Miral) — Thu, 15 Jun 2017 17:55:00 +0000

1. event.stopPropagation() stops an event from bubbling up the event chain

2. event.preventDefault() will only prevent browser’s default action on that event from occurring, but the event still propogates up the event chain.

Example

$("#myDiv").click(function() {
alert('click on #myDiv');
});

$("#divButton").click(function(e) {
alert('button click');
e.stopPropagation();
});

SSL Certificate err

noreply@blogger.com (Miral) — Fri, 02 Dec 2011 19:58:00 +0000

{http://xml.apache.org/axis/}stackTrace:javax.net.ssl.SSLException: java.lang.RuntimeException: Unexpected error: java.security.InvalidAlgorithmParameterException: the trustAnchors parameter must be non-empty at com.sun.net.ssl.internal.ssl.Alerts.getSSLException(Alerts.java:190) at com.sun.net.ssl.internal.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1649) at com.sun.net.ssl.internal.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1612) at com.sun.net.ssl.internal.ssl.SSLSocketImpl.handleException(SSLSocketImpl.java:1595) at com.sun.net.ssl.internal.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1172) at com.sun.net.ssl.internal.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1149) at org.apache.axis.components.net.JSSESocketFactory.create(JSSESocketFactory.java:186) at org.apache.axis.transport.http.HTTPSender.getSocket(HTTPSender.java:191) at org.apache.axis.transport.http.HTTPSender.writeToSocket(HTTPSender.java:404) at org.apache.axis.transport.http.HTTPSender.invoke(HTTPSender.java:138) at org.apache.axis.strategies.InvocationStrategy.visit(InvocationStrategy.java:32)

Comments:

Check the truststore path in a .properties file it should be on correct location?
You can try (double escape \) in that path for windows machine.

Detecting an undefined object in JavaScript

noreply@blogger.com (Miral) — Thu, 20 Oct 2011 20:42:00 +0000


typeof allows the identifier to never been declared before

if (typeof obj == "undefined")

instead of

if(obj == null) // will throw an error due to never declared

How to stop caching with jQuery ($.get(), $.ajax() etc) and javascript

noreply@blogger.com (Miral) — Wed, 31 Aug 2011 17:22:00 +0000

To make it unique for each passes, we can place in a random number behind the url as shown below

$.get('remoteUrl.do?'+Math.random()+, function(data){

	$('#msg'+id).html(data);

}, 'html');

Set cache:false

$.ajax({

	url: 'remoteUrl.do',

	cache: false,

	success: function(data){

		$('#resultDiv').append(data);

	} });

$.ajaxSetup({

	cache: false

});

Disable caching using html meta tag:

<meta equiv="cache-control" content="no-cache"><meta equiv="expires" content="0"><meta equiv="pragma" content="no-cache">

org.hibernate.PropertyAccessException

noreply@blogger.com (Miral) — Wed, 31 Aug 2011 14:58:00 +0000

nested exception is org.hibernate.PropertyAccessException: Exception occurred inside getter of Hibernate Object

Reason:

Nullable database column was mapped to a primitive type property

The Hibernate type is not castable to the property type (or vice-versa)

Tomcat - JDBC driver unregisted when the web application stops

noreply@blogger.com (Miral) — Wed, 13 Jul 2011 19:07:00 +0000

SEVERE: A web application registered the JBDC driver [oracle.jdbc.driver.OracleDriver] but failed to unregister it when the web application was stoppe

Solution:

Glassfish v2( JDBC Connection Pool, JNDI)

noreply@blogger.com (Miral) — Tue, 29 Jun 2010 19:42:00 +0000

Step 1:
Place database driver in glassfish lib dir. (e.g. lib/mysql-jdbc-5.1.11.jar) and restart server.

Step 2:
Login to Admin Console: http:\\localhost:4848\
Goto Resource > JDBC > Connection Pool
Provide Name, Select Database vendor and Select Resource Type

Step 3:
Enter DataSource class name (Database driver)
Change other settings as you want

Save and Ping
:) "Ping Succeed"

Connection Pool is ready

Converter - Convert MS Word/Excel to PDF

noreply@blogger.com (Miral) — Thu, 27 May 2010 22:29:00 +0000

Converts MS Word to PDF, image etc
Converts MS Excel Spreadsheet to PDF, image etc

Supported formats, MS Word, Excel, Powerpoint, Txt, Csv, Flash, ODT, RTF, PDF.. etc.

Here is the code:

long startTime1 = System.currentTimeMillis();

// connect to an OpenOffice.org instance running on port 8100
OpenOfficeConnection connection = new SocketOpenOfficeConnection(SocketOpenOfficeConnection.DEFAULT_PORT);
connection.connect();
DocumentConverter converter1 = new OpenOfficeDocumentConverter(connection);

File inputFile = new File("C:\\Miral\\temp\\myDocument.doc"));
File outputFile = new File("C:\\Miral\\temp\\myPortDocument.pdf");
totalFileSize+=(inputFile.length()/1024*100000)/100000;
converter1.convert(inputFile, outputFile);

System.out.println("Total File Size(kb): "+totalFileSize);
long endTime1 = System.currentTimeMillis();
System.out.println("Conversion Time: "+(endTime1-startTime1));
// close the connection
connection.disconnect();

iBatis (MyBatis)

noreply@blogger.com (Miral) — Tue, 27 Apr 2010 19:35:00 +0000

How to call stored procedure in iBatis?

You can execute stored procedure via SqlMap xml file.
See the folloing example:


<procedure id="getItemInfo" resultClass="Items" parameterMap="getItemInfoCall">
{ call getEmp( #invoiceNo# ) }
</procedure>

<parameterMap id="getItemInfoCall" class="map">
<parameter property="invoiceNo" jdbcType="INT" javaType="java.lang.Integer" mode="IN"/>
</parameterMap>

Reader rd = Resources.getResourceAsReader("SqlMapConfig.xml");

SqlMapClient smclient = SqlMapClientBuilder.buildSqlMapClient(rd);

int invoiceNo = 1;

System.out.println("Getting item information from db");

Items itm = (Items)smclient .queryForObject ("Items.getItemInfo", invoiceNo);

Struts 2 Validation Annotation

noreply@blogger.com (Miral) — Mon, 03 Aug 2009 16:39:00 +0000

This post will show how to use Annotation based validation in Struts 2. For this example I used the add transaction part of google's portfolio manager (noticed that they do not have validations over there). Struts 2 provides a number of validators for XML based validation rules. All of them have respective annotations defined and can be used in place of XML validation rules. In the example, we will use the @RequiredStringValidator, @RegexFieldValidator and also see how to parameterize messages when using annotations.

Follow these steps to implement the example ... There's more

1. Create a dynamic web project in Eclipse.
2. Copy the following jar files into the WEB-INF/lib directory, all these files are available with sturts download.
* struts2-core-2.0.11.1.jar
* xwork-2.0.4.jar
* freemarker-2.3.8.jar
* commons-logging-1.1.1.jar
* ognl-2.6.11.jar
3. Update your web deployment desciptor to include the sturts filter dispatcher.

WEB-INF/web.xml

4. Create the input JSP : transactions.jsp

<%@ taglib prefix="s" uri="/struts-tags"%> <s:form action="addTransaction" validate="true" method="post"> <s:fielderror> </s:fielderror> </s:form> <table> <tbody><tr> <td>Symbol</td> <td><s:textfield name="symbol"></s:textfield> </td> </tr> <tr> <td>Type</td> <td><s:select name="type" list="#{'':'Select One', 'BUY':'Buy','SELL':'Sell','BUY_COVER':'Buy to Cover','SELL_SHORT':'Sell Short'}"> </s:select></td> </tr> <tr> <td>Date</td> <td><s:textfield name="date"></s:textfield> </td> </tr> <tr> <td>Number of Shares</td> <td><s:textfield name="numberOfShares"></s:textfield> </td> </tr> <tr> <td>Price</td> <td><s:textfield name="price"></s:textfield> </td> </tr> <tr> <td>Commission</td> <td><s:textfield name="comission"></s:textfield> </td> </tr> <tr> <td>Notes</td> <td><s:textfield name="notes"></s:textfield> </td> </tr> <tr> <td colspan="2"> <s:submit name="submit" value="submit"></s:submit> <s:submit name="submitNoValidate" value="submit without validation" method="noValidation"></s:submit> </td> </tr> </tbody></table>

Note: The method="noValidation" indicates to struts that on submission, the noValidation() method will be invoked on the AddTransactionAction class.

5. Create the output JSP : done.jsp

<%@ taglib prefix="s" uri="/struts-tags"%> <s:bean name="actions.AddTransactionAction" id="addTransaction"></s:bean> <table> <tbody><tr> <td colspan="2">The following transaction has been added to your portfolio</td> </tr> <tr> <td>Symbol</td> <td><s:label name="symbol" value="%{symbol}"></s:label> </td> </tr> <tr> <td>Type</td> <td><s:label name="type" value="%{type}"> </s:label></td> </tr> <tr> <td>Date</td> <td><s:label name="date" value="%{date}"></s:label> </td> </tr> <tr> <td>Number of Shares</td> <td><s:label name="numberOfShares" value="%{numberOfShares}"></s:label> </td> </tr> <tr> <td>Price</td> <td><s:label name="price" value="%{price}"></s:label> </td> </tr> <tr> <td>Commission</td> <td><s:label name="comission" value="%{comission}"></s:label> </td> </tr> <tr> <td>Notes</td> <td><s:label name="notes" value="%{notes}"></s:label> </td> </tr> </tbody></table>

6. Create the Action class :AddTransactionAction.java

package actions;

import org.apache.struts2.interceptor.validation.SkipValidation;

import com.opensymphony.xwork2.ActionSupport;
import com.opensymphony.xwork2.validator.annotations.RegexFieldValidator;
import com.opensymphony.xwork2.validator.annotations.RequiredStringValidator;
import com.opensymphony.xwork2.validator.annotations.ValidatorType;
import com.opensymphony.xwork2.validator.annotations.Validation;

@Validation
public class AddTransactionAction extends ActionSupport {

private String symbol;
private String type;
private String date;
private String numberOfShares;
private String price;
private String comission;
private String notes;

public String execute() throws Exception {
System.out.println("In Execute");

return SUCCESS;
}

@SkipValidation
public String noValidation() throws Exception {
System.out.println("In Novalidation");
return SUCCESS;
}

public String getSymbol() {
return symbol;
}

@RequiredStringValidator(type = ValidatorType.FIELD, message = "Symbol Required")
public void setSymbol(String symbol) {
this.symbol = symbol;
}

public String getType() {
return type;
}

@RequiredStringValidator(type = ValidatorType.FIELD, message = "Type Required")
public void setType(String type) {
this.type = type;
}

public String getDate() {
return date;
}

@RequiredStringValidator(type = ValidatorType.FIELD, message = "Date Required")
@RegexFieldValidator(type=ValidatorType.FIELD, message="",key="date.error.message", expression = "[0-9][0-9]/[0-9][0-9]/[1-9][0-9][0-9][0-9]")
public void setDate(String date) {
this.date = date;
}

public String getNumberOfShares() {
return numberOfShares;
}

@RequiredStringValidator(type = ValidatorType.FIELD, message = " Number of Shares Required")
public void setNumberOfShares(String numberOfShares) {
this.numberOfShares = numberOfShares;
}

public String getPrice() {
return price;
}

@RequiredStringValidator(type = ValidatorType.FIELD, message = "Price Required")
public void setPrice(String price) {
this.price = price;
}

public String getComission() {
return comission;
}

@RequiredStringValidator(type = ValidatorType.FIELD, message = "Comission Required")
public void setComission(String comission) {
this.comission = comission;
}

public String getNotes() {
return notes;
}

public void setNotes(String notes) {
this.notes = notes;
}
}

Note:
* The annotation @Validation is used to indicate that the current action might need validation. The validations on a method level can be skipped using the @SkipValidation annotation on the method.
* The method noValidations() uses the @SkipValidation annotation, you can see this when you click on "Submit without validation" in the JSP
* The @RequiredStringValidator annotation is used to indicate a Required Strint similar to the following xml rule

* On the date field, I used a @RegexFieldValidator annotation, so that the date field will be mandated to have a given format.
* Parameterized messages: You will notice that the message attribute of the @RegexFieldValidator is set to an empty string, while the key is set to a value. This is due to the fact that the message attribute is mandatory, and the key attribute is used to denote the message key from the properties files. The parameters can be retrieved in the properties files using the ${date} notation where the "date" variable is expected to available in the value stack.

7. Create a definition for the action in struts.xml

Note: The result with name "input" is because the validator returns the result to input when validation fails.
8. Create the properties file for messages

date.error.message=Date ${date} is not properly formatted.

package.properties

Note: In the properties file, ${date} is used to retrieve the "date" value from the value stack, this is the way Struts 2 supports parameterization.

9. Create the struts.properties file to set the theme to simple theme, so that you have more control how the UI components are laid out.

struts.ui.theme=simple

struts.properties

Glassfish: Add Cluster Support

noreply@blogger.com (Miral) — Thu, 23 Jul 2009 22:07:00 +0000

Start your domain
Command: asadmin start-domain domain1

You will see message:
Domain does not support application server clusters and other standalone instances.

Goto: http://localhost:4848/

Go to the Application Server tree node, on the right hand side, you will see the 'Add Cluster Support' button. Click on this button

The next page will show you the implication about this action. Click OK

You will see that the profile has been successfully upgraded and server restart is required

Now restart your server.

You will see message:
Domain supports application server clusters and other standalone instances.

JQuery

noreply@blogger.com (Miral) — Fri, 10 Jul 2009 19:44:00 +0000

jQuery is a Open source JavaScript Library.

jQuery is easy to learn.

Fast, Easy to use, Easy-to-use AJAX (I love the $.ajaxSetup() function)
Nice Event handlers
CSS selectors

features:

* HTML element selections
* HTML element manipulation
* CSS manipulation
* HTML event functions
* JavaScript Effects and animations
* HTML DOM traversal and modification
* AJAX
* Utilities

Integrate Birt Report Engine To Your Application

noreply@blogger.com (Miral) — Tue, 05 May 2009 15:39:00 +0000

Setup

1. Download Birt Runtime

2. Copy all the jars in the birt-runtime/ReportEngine/lib directory from the Report Engine download into your ApplicationRoot/WEB-INF/lib directory.

3. Create a directory named platform in your WEB-INF folder.

4. Copy the birt-runtime/Report Engine/plugins and birt-runtime/ReportEngine/configuration directories to the platform directory you just created.

5. Copy iText.jar to the platform/plugins/com.lowagie.itext/lib directory. If the directory does not exist, create it.

6. Copy servlet.jar into WEB-INF/lib

* BirtConfig.properties - Configuration properties for the Engine.Place it to /WEB-INF/classes folder
* BirtEngine.java - Class used to initialize the Report Engine.
* WebReport.java - The servlet that handles report generation on a GET command.
* Copy Database driver class to

BirtConfig.properties

logDirectory=c:/temp

logLevel=FINEST

BirtEngine.java

import java.io.InputStream;
import java.io.IOException;
import java.util.Properties;
import java.util.logging.Level;
import org.eclipse.birt.report.engine.api.EngineConfig;
import org.eclipse.birt.report.engine.api.IReportEngine;
import javax.servlet.*;
import org.eclipse.birt.core.framework.PlatformServletContext;
import org.eclipse.birt.core.framework.IPlatformContext;
import org.eclipse.birt.core.framework.Platform;
import org.eclipse.birt.core.exception.BirtException;
import org.eclipse.birt.report.engine.api.IReportEngineFactory;

public class BirtEngine {

private static IReportEngine birtEngine = null;

private static Properties configProps = new Properties();

private final static String configFile = "BirtConfig.properties";

public static synchronized void initBirtConfig() {

loadEngineProps();

}

public static synchronized IReportEngine getBirtEngine(ServletContext sc) {

if (birtEngine == null)
{

EngineConfig config = new EngineConfig();

if( configProps != null){

String logLevel = configProps.getProperty("logLevel");

Level level = Level.OFF;

if ("SEVERE".equalsIgnoreCase(logLevel))

{

level = Level.SEVERE;

} else if ("WARNING".equalsIgnoreCase(logLevel))

{

level = Level.WARNING;

} else if ("INFO".equalsIgnoreCase(logLevel))

{

level = Level.INFO;

} else if ("CONFIG".equalsIgnoreCase(logLevel))

{

level = Level.CONFIG;

} else if ("FINE".equalsIgnoreCase(logLevel))

{

level = Level.FINE;

} else if ("FINER".equalsIgnoreCase(logLevel))

{

level = Level.FINER;

} else if ("FINEST".equalsIgnoreCase(logLevel))

{

level = Level.FINEST;

} else if ("OFF".equalsIgnoreCase(logLevel))

{

level = Level.OFF;

}

config.setLogConfig(configProps.getProperty("logDirectory"), level);

}

config.setEngineHome("");

IPlatformContext context = new PlatformServletContext( sc );

config.setPlatformContext( context );

try

{

Platform.startup( config );

}

catch ( BirtException e )

{

e.printStackTrace( );

}

IReportEngineFactory factory = (IReportEngineFactory) Platform

.createFactoryObject( IReportEngineFactory.EXTENSION_REPORT_ENGINE_FACTORY );

birtEngine = factory.createReportEngine( config );

}

return birtEngine;

}

public static synchronized void destroyBirtEngine() {

if (birtEngine == null) {

return;

}

birtEngine.shutdown();

Platform.shutdown();

birtEngine = null;

}

public Object clone() throws CloneNotSupportedException {

throw new CloneNotSupportedException();

}

private static void loadEngineProps() {

try {

//Config File must be in classpath

ClassLoader cl = Thread.currentThread ().getContextClassLoader();

InputStream in = null;

in = cl.getResourceAsStream (configFile);

configProps.load(in);

in.close();

} catch (IOException e) {

e.printStackTrace();

}

}

}

WebReport.java

import java.io.IOException;
import java.io.PrintWriter;
import java.util.HashMap;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.eclipse.birt.report.engine.api.EngineConstants;
import org.eclipse.birt.report.engine.api.HTMLRenderContext;
import org.eclipse.birt.report.engine.api.HTMLRenderOption;
import org.eclipse.birt.report.engine.api.IReportRunnable;
import org.eclipse.birt.report.engine.api.IRunAndRenderTask;
import org.eclipse.birt.report.engine.api.IReportEngine;

public class WebReport extends HttpServlet {

private static final long serialVersionUID = 1L;

/**

* Constructor of the object.

*/

private IReportEngine birtReportEngine = null;

protected static Logger logger = Logger.getLogger( "org.eclipse.birt" );

public WebReport() {

super();

}

/**

* Destruction of the servlet.

*/

public void destroy() {

super.destroy();

BirtEngine.destroyBirtEngine();

}

/**

* The doGet method of the servlet.

*

*/

public void doGet(HttpServletRequest req, HttpServletResponse resp)

throws ServletException, IOException {

//get report name and launch the engine

resp.setContentType("text/html");

//resp.setContentType( "application/pdf" );

//resp.setHeader ("Content-Disposition","inline; filename=test.pdf");

String reportName = req.getParameter("ReportName");

ServletContext sc = req.getSession().getServletContext();

this.birtReportEngine = BirtEngine.getBirtEngine(sc);

//setup image directory

HTMLRenderContext renderContext = new HTMLRenderContext();

renderContext.setBaseImageURL(req.getContextPath()+"/images");

renderContext.setImageDirectory(sc.getRealPath("/images"));

logger.log( Level.FINE, "image directory " + sc.getRealPath("/images"));

System.out.println("stdout image directory " + sc.getRealPath("/images"));

HashMap contextMap = new HashMap();

contextMap.put( EngineConstants.APPCONTEXT_HTML_RENDER_CONTEXT, renderContext );

IReportRunnable design;

try

{

//Open report design

design = birtReportEngine.openReportDesign( sc.getRealPath("/Reports")+"/"+reportName );

//create task to run and render report

IRunAndRenderTask task = birtReportEngine.createRunAndRenderTask( design );

task.setAppContext( contextMap );

//set output options

HTMLRenderOption options = new HTMLRenderOption();

options.setOutputFormat(HTMLRenderOption.OUTPUT_FORMAT_HTML);

//options.setOutputFormat(HTMLRenderOption.OUTPUT_FORMAT_PDF);

options.setOutputStream(resp.getOutputStream());

task.setRenderOption(options);

//run report

task.run();

task.close();

}catch (Exception e){
e.printStackTrace();
throw new ServletException( e );
}

}

/**

* The doPost method of the servlet.

*/

public void doPost(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

response.setContentType("text/html");

PrintWriter out = response.getWriter();
out.println("");
out.println("");
out.println(" ");
out.println(" ");
out.println(" Post does nothing");
out.println(" ");
out.println("");
out.flush();
out.close();

}

/**

* Initialization of the servlet.

*

* @throws ServletException if an error occure

*/

public void init() throws ServletException {

BirtEngine.initBirtConfig();

}

}

Frameworks Comparision

noreply@blogger.com (Miral) — Fri, 01 May 2009 21:11:00 +0000

Ajax support

JSF: No Ajax support, use ICEfaces and Ajax4JSF

Stripes: No libraries, supports streaming results

Struts 2: Dojo built-in, plugins for GWT, JSON

Spring MVC: No libraries, use DWR

Tapestry: Dojo built-in in 4.1

Bookmarking and URLs
JSF does a POST for everything - URLs not even considered

Struts 2 has namespaces - makes it easy

Spring MVC allows full URL control

Tapestry still has somewhat ugly URLs

Validation

JSF has ugly default messages, but easiest to configure

Spring MVC allows you to use Commons Validator - a mature solution

Struts 2 uses OGNL for powerful expressions - clientside only works when specifying rules on Actions

Tapestry has very robust validation - good messages without need to customize

Stripes and Wicket do validation in Java - no client-side

Testability

Spring and Struts 2 allow easy testing with mocks (e.g. EasyMock, jMock, Spring Mocks)

JSF page classes can be easily tested and actually look a lot like Struts 2 actions

Struts 1 Vs Struts 2

noreply@blogger.com (Miral) — Fri, 01 May 2009 21:11:00 +0000

Struts 1 Vs Struts 2

Action classes

Struts 1 requires Action classes to extend an abstract base class. A common problem in Struts 1 is programming to abstract classes instead of interfaces.

An Struts 2 Action may implement an Action interface, along with other interfaces to enable optional and custom services. Struts 2 provides a base ActionSupport class to implement commonly used interfaces. Albeit, the Action interface is not required. Any POJO object with a execute signature can be used as an Struts 2 Action object.

Threading Model

Struts 1 Actions are singletons and must be thread-safe since there will only be one instance of a class to handle all requests for that Action. The singleton strategy places restrictions on what can be done with Struts 1 Actions and requires extra care to develop. Action resources must be thread-safe or synchronized.

Struts 2 Action objects are instantiated for each request, so there are no thread-safety issues. (In practice, servlet containers generate many throw-away objects per request, and one more object does not impose a performance penalty or impact garbage collection.)

Servlet Dependency

Struts 1 Actions have dependencies on the servlet API since the HttpServletRequest and HttpServletResponse is passed to the execute method when an Action is invoked.

Struts 2 Actions are not coupled to a container. Most often the servlet contexts are represented as simple Maps, allowing Actions to be tested in isolation. Struts 2 Actions can still access the original request and response, if required. However, other architectural elements reduce or eliminate the need to access the HttpServetRequest or HttpServletResponse directly.

Testability

A major hurdle to testing Struts 1 Actions is that the execute method exposes the Servlet API. A third-party extension, Struts TestCase, offers a set of mock object for Struts 1.

Struts 2 Actions can be tested by instantiating the Action, setting properties, and invoking methods. Dependency Injection support also makes testing simpler.

Harvesting Input

Struts 1 uses an ActionForm object to capture input. Like Actions, all ActionForms must extend a base class. Since other JavaBeans cannot be used as ActionForms, developers often create redundant classes to capture input. DynaBeans can used as an alternative to creating conventional ActionForm classes, but, here too, developers may be redescribing existing JavaBeans.

Struts 2 uses Action properties as input properties, eliminating the need for a second input object. Input properties may be rich object types which may have their own properties. The Action properties can be accessed from the web page via the taglibs. Struts 2 also supports the ActionForm pattern, as well as POJO form objects and POJO Actions. Rich object types, including business or domain objects, can be used as input/output objects. The ModelDriven feature simplifies taglb references to POJO input objects.

Expression Language

Struts 1 integrates with JSTL, so it uses the JSTL EL. The EL has basic object graph traversal, but relatively weak collection and indexed property support.

Struts 2 can use JSTL, but the framework also supports a more powerful and flexible expression language called "Object Graph Notation Language" (OGNL).

Binding values into views

Struts 1 uses the standard JSP mechanism for binding objects into the page context for access.

Struts 2 uses a "ValueStack" technology so that the taglibs can access values without coupling your view to the object type it is rendering. The ValueStack strategy allows reuse of views across a range of types which may have the same property name but different property types.

Type Conversion

Struts 1 ActionForm properties are usually all Strings. Struts 1 uses Commons-Beanutils for type conversion. Converters are per-class, and not configurable per instance.

Struts 2 uses OGNL for type conversion. The framework includes converters for basic and common object types and primitives.

Validation

Struts 1 supports manual validation via a validate method on the ActionForm, or through an extension to the Commons Validator. Classes can have different validation contexts for the same class, but cannot chain to validations on sub-objects.

Struts 2 supports manual validation via the validate method and the XWork Validation framework. The Xwork Validation Framework supports chaining validation into sub-properties using the validations defined for the properties class type and the validation context.

Control Of Action Execution

Struts 1 supports separate Request Processors (lifecycles) for each module, but all the Actions in the module must share the same lifecycle.

Struts 2 supports creating different lifecycles on a per Action basis via Interceptor Stacks. Custom stacks can be created and used with different Actions, as needed.

JDBC using JNDI

noreply@blogger.com (Miral) — Fri, 24 Apr 2009 20:37:00 +0000

public class dbConnection {

public void testConnection(){
String sql = "select * from emp"; // query

Connection con = null;
Statement stmt = null;
ResultSet rs = null;

InitialContext cxt = new InitialContext();
DataSource dataSource = (DataSource) cxt.lookup("jdbc/myEmpDB"); // "jdbc/myEmpDB"get JNDI JDBC connection
con = dataSource.getConnection();

// run sql objects
stmt = con.createStatement();
rs = stmt.executeQuery(sql);

while (rs.next()) {
System.out.println("Emp Name : "+rs.getString("employeeName")));
}
}
}

JDBC (Java Database Connectivity) with MySQL

noreply@blogger.com (Miral) — Fri, 24 Apr 2009 20:28:00 +0000

public class dbConnection {

public void testConnection(){

String sql = "select * from emp"; // query
String conURL = "jdbc:mysql://localhost:3306/employeeDB"; // "employeeDB" is database name

Connection con = null;
Statement stmt = null;
ResultSet rs = null;

Class.forName("com.mysql.jdbc.Driver"); // create instance of mysql driver
con = DriverManager.getConnection(conURL);

stmt = con.createStatement();
rs = stmt.executeQuery(sql);

while (rs.next()) {
System.out.println("Emp Name : "+rs.getString("employeeName")));
}
}
}

Jasper Report

noreply@blogger.com (Miral) — Thu, 12 Feb 2009 14:44:00 +0000

Jasper Reportsis an open-source Java reporting library.
100% written in Java.
It compiles .jrxml (XML source) to .jasper (compiled) files, which in turn can be transformed into several output types including PDF, HTML, CSV, and XLS.
You can configure various data source: JDBC, EJB, POJO, Hibernate, XML.

Download Struts 2 Jasper Report Plugins

We need the following libraries: http://www.sourceforge.net/projects/jasperreports

jasperreports-version.jar
commons-*.jar
itext-version.jar
jdt-compiler.jar

Copy these libraries to your WEB-INF/lib directory

Code

Create Product JavaBean called Product.java

Create Action (MyJasperAction) which compiles and stream the datasource to jrxml which compiles and generate report.



public class MyJasperAction extends ActionSupport {

    /** create List to use as our JasperReports dataSource. */

    private List myList;

    public String execute() throws Exception {

        Product p1 = new Product(new Long(1), "Sony Camera", "149.99");

        Product p2 = new Product(new Long(2), "Fuji Camera", "99.99");

        // Store product in our dataSource list (normally would come from database).

        myList = new ArrayList();

        myList.add(p1);

        myList.add(p2);

        // Normally we would provide a pre-compiled .jrxml file

        // or check to make sure we don't compile on every request.

try {

JasperCompileManager.compileReportToFile(

"myapp/reports/jasper_template.jrxml",

"myapp/reports/compiled_template.jasper");

} catch (Exception e) {

e.printStackTrace();

return ERROR;

}

        return SUCCESS;

    public List getMyList() {

        return myList;

Struts.xml

define the jasper result type manually in struts.xml

Jasper Reports Pagination

noreply@blogger.com (Miral) — Mon, 05 Jan 2009 20:19:00 +0000

//IGNORE PAGINATION
// if (!format.equals(ReportFormat.PDF.toString()))
// parameters.put(JRParameter.IS_IGNORE_PAGINATION, Boolean.TRUE); // IGNORE PAGINATION BEFORE JRFillManager.fillReport

//PAGINATION
//exporter.setParameter(JRExporterParameter.PAGE_INDEX, new Integer(0));
//JRVariable[] jrVariables jasperReport.getVariables();
// retrive PAGE_COUNT Variable for total page and perfor paging on that

MySQL 5.0 Illegal mix of collations (latin1_swedish_ci,COERCIBLE) and (utf8_general_ci,IMPLICIT) for operation 'UNION'

noreply@blogger.com (Miral) — Thu, 05 Jun 2008 18:50:00 +0000

Illegal mix of collations (latin1_swedish_ci,COERCIBLE) and (utf8_general_ci,IMPLICIT) for operation 'UNION'

Above error in MySQL 5.0

Make change in my.cnf

default-character-set=latin1 to default-character-set=utf8

at two places

Restart your mysql server your error will solved.

Freemarker with sample code

noreply@blogger.com (Miral) — Thu, 29 Nov 2007 10:48:00 +0000

Freemarker:-

FreeMarker is a "template engine"; a generic tool to generate text output (anything from HTML to auto generated source code) based on templates. It's a Java package, a class library for Java programmers. It's not an application for end-users in itself, but something that programmers can embed into their products.

FreeMarker is designed to be practical for the generation of HTML Web pages, particularly by servlet-based applications following the MVC (Model View Controller) pattern. The idea behind using the MVC pattern for dynamic Web pages is that you separate the designers (HTML authors) from the programmers. Everybody works on what they are good at. Designers can change the appearance of a page without programmers having to change or recompile code, because the application logic (Java programs) and page design (FreeMarker templates) are separated. Templates do not become polluted with complex program fragments. This separation is useful even for projects where the programmer and the HTML page author is the same person, since it helps to keep the application clear and easily maintainable.

Although FreeMarker has some programming capabilities, it is not a full-blown programming language like PHP. Instead, Java programs prepare the data to be displayed (like issue SQL queries), and FreeMarker just generates textual pages that display the prepared data using templates

FreeMarker is not a Web application framework. It is suitable as a component in a Web application framework, but the FreeMarker engine itself knows nothing about HTTP or servlets. It simply generates text. As such, it is perfectly usable in non-web application environments as well. Note, however, that we provide out-of-the-box solutions for using FreeMarker as the view component of Model 2 frameworks (e.g. Struts), which also let you use JSP taglibs in the templates.

/**
* Sample code for generate freemarker template
*/

import java.io.File;
import java.io.StringWriter;
import freemarker.template.Template;
import freemarker.template.Configuration;
import org.apache.commons.io.FileUtils;
import com.custombeans.TemplateBean;
import com.helper.GenerateFileHelper;

class freemarkerDemo{

public static synchronized void generateTemplate() {
try {
Configuration config = new freemarker.template.Configuration().setServletContextForTemplateLoading(servletContext, "/WEB-INF/templates/");
Template tmpl =config.getTemplate("template.ftl");
StringWriter sw = new StringWriter();
Map bean = new HashMap();
bean.put("id",1);
bean.put("FirstName","Amin");
bean.put("LastName","Miral");
tmpl.process(bean, sw);

File resultFile = new File(CONTEXT.getRealPath("template.html"));
try {
FileUtils.writeStringToFile(resultFile, sw.getBuffer().toString(), "UTF-8");
} catch (Exception e) {
e.printStackTrace();
}
} catch (Exception e) {
e.printStackTrace();
}
}
}

EDITOR / IDE - Freemarker
Eclipse 3.x Syntax highlight, syntax error indicator, outline view, code completion for macro names and bean property names.

IntelliJ IDEA 8.0	A well-known feature-rich commercial Java IDE.
jEdit 4.1	jEdit is a Free programmer's text editor written in Java. It is highly customizable, extensible, and has an easy-to-use interface.
SitePad Pro 6	SitePad Pro is an Integrated Development Environment (IDE) for Java, HTML, VRML and other files. It's commercial software.

Struts 2 Help

noreply@blogger.com (Miral) — Sat, 06 Oct 2007 10:19:00 +0000

Interceptor:-

Interceptors can execute code before and after an Action is invoked. Most of the framework's core functionality is implemented as Interceptors. Features like double-submit guards, type conversion, object population, validation, file upload, page preparation, and more, are all implemented with the help of Interceptors. Each and every Interceptor is pluggable, so you can decide exactly which features an Action needs to support.

Interceptors can be configured on a per-action basis. Your own custom Interceptors can be mixed-and-matched with the Interceptors bundled with the framework. Interceptors "set the stage" for the Action classes, doing much of the "heavy lifting" before the Action executes.

Result Types

Most use cases can be divided into two phases. First, we need to change or query the application's state, and then we need to present an updated view of the application. The Action class manages the application's state, and the Result Type manages the view.

Predefined Result Types

The framework provides several implementations of the com.opensymphony.xwork2.Result interface, ready to use in your own applications.

Chain Result	Used for Action Chaining
Dispatcher Result	Used for web resource integration, including JSP integration
FreeMarker Result	Used for FreeMarker integration
HttpHeader Result	Used to control special HTTP behaviors
Redirect Result	Used to redirect to another URL (web resource)
Redirect Action Result	Used to redirect to another action mapping
Stream Result	Used to stream an InputStream back to the browser (usually for file downloads)
Velocity Result	Used for Velocity integration
XSL Result	Used for XML/XSLT integration
PlainText Result	Used to display the raw content of a particular page (i.e jsp, HTML)
S2PLUGINS:Tiles Result	Used to provide Tiles integration

Optional

JasperReports Plugin

Used for JasperReports Tutorial integration

Optional, third-party plugin

Additional Result Types can be created and plugged into an application by implementing the com.opensymphony.xwork2.Result interface. Custom Result Types might include generating an email or JMS message, generating images, and so forth.

Editors / IDE for Struts 2

NetBeans
IDEA IntelliJ
Eclipse

Above Editors/IDE helps you to build your Struts 2 project.
Build your struts 2 project using above IDE.

HTTP Status Code Definitions

noreply@blogger.com (Miral) — Sat, 06 Oct 2007 06:33:00 +0000

HTTP Status Code Definitions :

HTTP, Hypertext Transfer Protocol, is the method by which clients (i.e. you) and servers communicate. Each Status-Code is described below, including a description of which method(s) it can follow and any metainformation required in the response.

Informational 1xx :

This class of status code indicates a provisional response, consisting only of the Status-Line and optional headers, and is terminated by an empty line. There are no required headers for this class of status code. Since HTTP/1.0 did not define any 1xx status codes, servers MUST NOT send a 1xx response to an HTTP/1.0 client except under experimental conditions.

A client MUST be prepared to accept one or more 1xx status responses prior to a regular response, even if the client does not expect a 100 (Continue) status message. Unexpected 1xx status responses MAY be ignored by a user agent.

Proxies MUST forward 1xx responses, unless the connection between the proxy and its client has been closed, or unless the proxy itself requested the generation of the 1xx response. (For example, if a

proxy adds a "Expect: 100-continue" field when it forwards a request, then it need not forward the corresponding 100 (Continue) response(s).)

100 Continue :

The client SHOULD continue with its request. This interim response is used to inform the client that the initial part of the request has been received and has not yet been rejected by the server. The client SHOULD continue by sending the remainder of the request or, if the request has already been completed, ignore this response. The server MUST send a final response after the request has been completed. See section 8.2.3 for detailed discussion of the use and handling of this status code.

101 Switching Protocols :

The server understands and is willing to comply with the client's request, via the Upgrade message header field (section 14.42), for a change in the application protocol being used on this connection. The server will switch protocols to those defined by the response's Upgrade header field immediately after the empty line which terminates the 101 response.

The protocol SHOULD be switched only when it is advantageous to do so. For example, switching to a newer version of HTTP is advantageous over older versions, and switching to a real-time, synchronous protocol might be advantageous when delivering resources that use such features.

Successful 2xx :

This class of status code indicates that the client's request was successfully received, understood, and accepted.

200 OK :

The request has succeeded. The information returned with the response is dependent on the method used in the request, for example:

GET an entity corresponding to the requested resource is sent in the response;

HEAD the entity-header fields corresponding to the requested resource are sent in the response without any message-body;

POST an entity describing or containing the result of the action;

TRACE an entity containing the request message as received by the end server.

201 Created :

The request has been fulfilled and resulted in a new resource being created. The newly created resource can be referenced by the URI(s) returned in the entity of the response, with the most specific URI for the resource given by a Location header field. The response SHOULD include an entity containing a list of resource characteristics and location(s) from which the user or user agent can choose the one most appropriate. The entity format is specified by the media type given in the Content-Type header field. The origin server MUST create the resource before returning the 201 status code. If the action cannot be carried out immediately, the server SHOULD respond with 202 (Accepted) response instead.

A 201 response MAY contain an ETag response header field indicating the current value of the entity tag for the requested variant just created, see section 14.19.

202 Accepted :

The request has been accepted for processing, but the processing has not been completed. The request might or might not eventually be acted upon, as it might be disallowed when processing actually takes place. There is no facility for re-sending a status code from an asynchronous operation such as this.

The 202 response is intentionally non-committal. Its purpose is to allow a server to accept a request for some other process (perhaps a batch-oriented process that is only run once per day) without requiring that the user agent's connection to the server persist until the process is completed. The entity returned with this response SHOULD include an indication of the request's current status and either a pointer to a status monitor or some estimate of when the user can expect the request to be fulfilled.

203 Non-Authoritative Information :

The returned metainformation in the entity-header is not the definitive set as available from the origin server, but is gathered from a local or a third-party copy. The set presented MAY be a subset or superset of the original version. For example, including local annotation information about the resource might result in a superset of the metainformation known by the origin server. Use of this response code is not required and is only appropriate when the response would otherwise be 200 (OK).

204 No Content :

The server has fulfilled the request but does not need to return an entity-body, and might want to return updated metainformation. The response MAY include new or updated metainformation in the form of entity-headers, which if present SHOULD be associated with the requested variant.

If the client is a user agent, it SHOULD NOT change its document view from that which caused the request to be sent. This response is primarily intended to allow input for actions to take place without causing a change to the user agent's active document view, although any new or updated metainformation SHOULD be applied to the document currently in the user agent's active view.

The 204 response MUST NOT include a message-body, and thus is always terminated by the first empty line after the header fields.

205 Reset Content :

The server has fulfilled the request and the user agent SHOULD reset the document view which caused the request to be sent. This response is primarily intended to allow input for actions to take place via user input, followed by a clearing of the form in which the input is given so that the user can easily initiate another input action. The response MUST NOT include an entity.

206 Partial Content :

The server has fulfilled the partial GET request for the resource. The request MUST have included a Range header field (section 14.35) indicating the desired range, and MAY have included an If-Range header field (section 14.27) to make the request conditional.

The response MUST include the following header fields:

- Either a Content-Range header field (section 14.16) indicating
the range included with this response, or a multipart/byteranges
Content-Type including Content-Range fields for each part. If a
Content-Length header field is present in the response, its
value MUST match the actual number of OCTETs transmitted in the
message-body.

- Date

- ETag and/or Content-Location, if the header would have been sent
in a 200 response to the same request

- Expires, Cache-Control, and/or Vary, if the field-value might
differ from that sent in any previous response for the same
variant

If the 206 response is the result of an If-Range request that used a strong cache validator (see section 13.3.3), the response SHOULD NOT include other entity-headers. If the response is the result of an If-Range request that used a weak validator, the response MUST NOT include other entity-headers; this prevents inconsistencies between cached entity-bodies and updated headers. Otherwise, the response MUST include all of the entity-headers that would have been returned with a 200 (OK) response to the same request.

A cache MUST NOT combine a 206 response with other previously cached content if the ETag or Last-Modified headers do not match exactly, see 13.5.4.

A cache that does not support the Range and Content-Range headers MUST NOT cache 206 (Partial) responses.

Redirection 3xx :

This class of status code indicates that further action needs to be taken by the user agent in order to fulfill the request. The action required MAY be carried out by the user agent without interaction with the user if and only if the method used in the second request is GET or HEAD. A client SHOULD detect infinite redirection loops, since such loops generate network traffic for each redirection.

Note: previous versions of this specification recommended a
maximum of five redirections. Content developers should be aware
that there might be clients that implement such a fixed
limitation.

300 Multiple Choices :

The requested resource corresponds to any one of a set of representations, each with its own specific location, and agent- driven negotiation information (section 12) is being provided so that the user (or user agent) can select a preferred representation and redirect its request to that location.

Unless it was a HEAD request, the response SHOULD include an entity containing a list of resource characteristics and location(s) from which the user or user agent can choose the one most appropriate. The entity format is specified by the media type given in the Content- Type header field. Depending upon the format and the capabilities of

the user agent, selection of the most appropriate choice MAY be performed automatically. However, this specification does not define any standard for such automatic selection.

If the server has a preferred choice of representation, it SHOULD include the specific URI for that representation in the Location field; user agents MAY use the Location field value for automatic redirection. This response is cacheable unless indicated otherwise.

301 Moved Permanently :

The requested resource has been assigned a new permanent URI and any future references to this resource SHOULD use one of the returned URIs. Clients with link editing capabilities ought to automatically re-link references to the Request-URI to one or more of the new references returned by the server, where possible. This response is cacheable unless indicated otherwise.

The new permanent URI SHOULD be given by the Location field in the response. Unless the request method was HEAD, the entity of the response SHOULD contain a short hypertext note with a hyperlink to the new URI(s).

If the 301 status code is received in response to a request other than GET or HEAD, the user agent MUST NOT automatically redirect the request unless it can be confirmed by the user, since this might change the conditions under which the request was issued.

Note: When automatically redirecting a POST request after
receiving a 301 status code, some existing HTTP/1.0 user agents
will erroneously change it into a GET request.

302 Found :

The requested resource resides temporarily under a different URI. Since the redirection might be altered on occasion, the client SHOULD continue to use the Request-URI for future requests. This response is only cacheable if indicated by a Cache-Control or Expires header field.

The temporary URI SHOULD be given by the Location field in the response. Unless the request method was HEAD, the entity of the response SHOULD contain a short hypertext note with a hyperlink to the new URI(s).

If the 302 status code is received in response to a request other than GET or HEAD, the user agent MUST NOT automatically redirect the request unless it can be confirmed by the user, since this might change the conditions under which the request was issued.

Note: RFC 1945 and RFC 2068 specify that the client is not allowed
to change the method on the redirected request. However, most
existing user agent implementations treat 302 as if it were a 303
response, performing a GET on the Location field-value regardless
of the original request method. The status codes 303 and 307 have
been added for servers that wish to make unambiguously clear which
kind of reaction is expected of the client.

303 See Other :

The response to the request can be found under a different URI and SHOULD be retrieved using a GET method on that resource. This method exists primarily to allow the output of a POST-activated script to redirect the user agent to a selected resource. The new URI is not a substitute reference for the originally requested resource. The 303 response MUST NOT be cached, but the response to the second (redirected) request might be cacheable.

The different URI SHOULD be given by the Location field in the response. Unless the request method was HEAD, the entity of the response SHOULD contain a short hypertext note with a hyperlink to the new URI(s).

Note: Many pre-HTTP/1.1 user agents do not understand the 303
status. When interoperability with such clients is a concern, the
302 status code may be used instead, since most user agents react
to a 302 response as described here for 303.

304 Not Modified :

If the client has performed a conditional GET request and access is allowed, but the document has not been modified, the server SHOULD respond with this status code. The 304 response MUST NOT contain a message-body, and thus is always terminated by the first empty line after the header fields.

The response MUST include the following header fields:

- Date, unless its omission is required by section 14.18.1

If a clockless origin server obeys these rules, and proxies and clients add their own Date to any response received without one (as already specified by [RFC 2068], section 14.19), caches will operate correctly.

- ETag and/or Content-Location, if the header would have been sent
in a 200 response to the same request

- Expires, Cache-Control, and/or Vary, if the field-value might
differ from that sent in any previous response for the same
variant

If the conditional GET used a strong cache validator (see section 13.3.3), the response SHOULD NOT include other entity-headers. Otherwise (i.e., the conditional GET used a weak validator), the response MUST NOT include other entity-headers; this prevents inconsistencies between cached entity-bodies and updated headers.

If a 304 response indicates an entity not currently cached, then the cache MUST disregard the response and repeat the request without the conditional.

If a cache uses a received 304 response to update a cache entry, the cache MUST update the entry to reflect any new field values given in the response.

305 Use Proxy :

The requested resource MUST be accessed through the proxy given by the Location field. The Location field gives the URI of the proxy. The recipient is expected to repeat this single request via the proxy. 305 responses MUST only be generated by origin servers.

Note: RFC 2068 was not clear that 305 was intended to redirect a
single request, and to be generated by origin servers only. Not
observing these limitations has significant security consequences.

306 (Unused) :

The 306 status code was used in a previous version of the specification, is no longer used, and the code is reserved.

307 Temporary Redirect

The requested resource resides temporarily under a different URI. Since the redirection MAY be altered on occasion, the client SHOULD continue to use the Request-URI for future requests. This response is only cacheable if indicated by a Cache-Control or Expires header field.

The temporary URI SHOULD be given by the Location field in the response. Unless the request method was HEAD, the entity of the response SHOULD contain a short hypertext note with a hyperlink to the new URI(s) , since many pre-HTTP/1.1 user agents do not understand the 307 status. Therefore, the note SHOULD contain the information necessary for a user to repeat the original request on the new URI.

If the 307 status code is received in response to a request other than GET or HEAD, the user agent MUST NOT automatically redirect the request unless it can be confirmed by the user, since this might change the conditions under which the request was issued.

Client Error 4xx :

The 4xx class of status code is intended for cases in which the client seems to have erred. Except when responding to a HEAD request, the server SHOULD include an entity containing an explanation of the error situation, and whether it is a temporary or permanent condition. These status codes are applicable to any request method. User agents SHOULD display any included entity to the user.

If the client is sending data, a server implementation using TCP SHOULD be careful to ensure that the client acknowledges receipt of the packet(s) containing the response, before the server closes the input connection. If the client continues sending data to the server after the close, the server's TCP stack will send a reset packet to the client, which may erase the client's unacknowledged input buffers before they can be read and interpreted by the HTTP application.

400 Bad Request :

The request could not be understood by the server due to malformed syntax. The client SHOULD NOT repeat the request without modifications.

401 Unauthorized :

The request requires user authentication. The response MUST include a WWW-Authenticate header field (section 14.47) containing a challenge applicable to the requested resource. The client MAY repeat the request with a suitable Authorization header field (section 14.8). If the request already included Authorization credentials, then the 401 response indicates that authorization has been refused for those credentials. If the 401 response contains the same challenge as the prior response, and the user agent has already attempted authentication at least once, then the user SHOULD be presented the entity that was given in the response, since that entity might include relevant diagnostic information. HTTP access authentication is explained in "HTTP Authentication: Basic and Digest Access Authentication" [43].

402 Payment Required :

This code is reserved for future use.

403 Forbidden :

The server understood the request, but is refusing to fulfill it. Authorization will not help and the request SHOULD NOT be repeated. If the request method was not HEAD and the server wishes to make public why the request has not been fulfilled, it SHOULD describe the reason for the refusal in the entity. If the server does not wish to make this information available to the client, the status code 404 (Not Found) can be used instead.

404 Not Found :

The server has not found anything matching the Request-URI. No indication is given of whether the condition is temporary or permanent. The 410 (Gone) status code SHOULD be used if the server knows, through some internally configurable mechanism, that an old resource is permanently unavailable and has no forwarding address. This status code is commonly used when the server does not wish to reveal exactly why the request has been refused, or when no other response is applicable.

405 Method Not Allowed :

The method specified in the Request-Line is not allowed for the resource identified by the Request-URI. The response MUST include an Allow header containing a list of valid methods for the requested resource.

406 Not Acceptable :

The resource identified by the request is only capable of generating response entities which have content characteristics not acceptable according to the accept headers sent in the request.

Unless it was a HEAD request, the response SHOULD include an entity containing a list of available entity characteristics and location(s) from which the user or user agent can choose the one most appropriate. The entity format is specified by the media type given in the Content-Type header field. Depending upon the format and the capabilities of the user agent, selection of the most appropriate choice MAY be performed automatically. However, this specification does not define any standard for such automatic selection.

Note: HTTP/1.1 servers are allowed to return responses which are
not acceptable according to the accept headers sent in the
request. In some cases, this may even be preferable to sending a
406 response. User agents are encouraged to inspect the headers of
an incoming response to determine if it is acceptable.

If the response could be unacceptable, a user agent SHOULD temporarily stop receipt of more data and query the user for a decision on further actions.

407 Proxy Authentication Required :

This code is similar to 401 (Unauthorized), but indicates that the client must first authenticate itself with the proxy. The proxy MUST return a Proxy-Authenticate header field (section 14.33) containing a challenge applicable to the proxy for the requested resource. The client MAY repeat the request with a suitable Proxy-Authorization header field (section 14.34). HTTP access authentication is explained in "HTTP Authentication: Basic and Digest Access Authentication" [43].

408 Request Timeout :

The client did not produce a request within the time that the server was prepared to wait. The client MAY repeat the request without modifications at any later time.

409 Conflict :

The request could not be completed due to a conflict with the current state of the resource. This code is only allowed in situations where it is expected that the user might be able to resolve the conflict and resubmit the request. The response body SHOULD include enough

information for the user to recognize the source of the conflict. Ideally, the response entity would include enough information for the user or user agent to fix the problem; however, that might not be possible and is not required.

Conflicts are most likely to occur in response to a PUT request. For example, if versioning were being used and the entity being PUT included changes to a resource which conflict with those made by an earlier (third-party) request, the server might use the 409 response to indicate that it can't complete the request. In this case, the response entity would likely contain a list of the differences between the two versions in a format defined by the response Content-Type.

410 Gone :

The requested resource is no longer available at the server and no forwarding address is known. This condition is expected to be considered permanent. Clients with link editing capabilities SHOULD delete references to the Request-URI after user approval. If the server does not know, or has no facility to determine, whether or not the condition is permanent, the status code 404 (Not Found) SHOULD be used instead. This response is cacheable unless indicated otherwise.

The 410 response is primarily intended to assist the task of web maintenance by notifying the recipient that the resource is intentionally unavailable and that the server owners desire that remote links to that resource be removed. Such an event is common for limited-time, promotional services and for resources belonging to individuals no longer working at the server's site. It is not necessary to mark all permanently unavailable resources as "gone" or to keep the mark for any length of time -- that is left to the discretion of the server owner.

411 Length Required :

The server refuses to accept the request without a defined Content- Length. The client MAY repeat the request if it adds a valid Content-Length header field containing the length of the message-body in the request message.

412 Precondition Failed :

The precondition given in one or more of the request-header fields evaluated to false when it was tested on the server. This response code allows the client to place preconditions on the current resource metainformation (header field data) and thus prevent the requested method from being applied to a resource other than the one intended.

413 Request Entity Too Large :

The server is refusing to process a request because the request entity is larger than the server is willing or able to process. The server MAY close the connection to prevent the client from continuing the request.

If the condition is temporary, the server SHOULD include a Retry- After header field to indicate that it is temporary and after what time the client MAY try again.

414 Request-URI Too Long :

The server is refusing to service the request because the Request-URI is longer than the server is willing to interpret. This rare condition is only likely to occur when a client has improperly converted a POST request to a GET request with long query information, when the client has descended into a URI "black hole" of redirection (e.g., a redirected URI prefix that points to a suffix of itself), or when the server is under attack by a client attempting to exploit security holes present in some servers using fixed-length buffers for reading or manipulating the Request-URI.

415 Unsupported Media Type :

The server is refusing to service the request because the entity of the request is in a format not supported by the requested resource for the requested method.

416 Requested Range Not Satisfiable :

A server SHOULD return a response with this status code if a request included a Range request-header field (section 14.35), and none of the range-specifier values in this field overlap the current extent of the selected resource, and the request did not include an If-Range request-header field. (For byte-ranges, this means that the first- byte-pos of all of the byte-range-spec values were greater than the current length of the selected resource.)

When this status code is returned for a byte-range request, the response SHOULD include a Content-Range entity-header field specifying the current length of the selected resource (see section 14.16). This response MUST NOT use the multipart/byteranges content- type.

417 Expectation Failed :

The expectation given in an Expect request-header field (see section 14.20) could not be met by this server, or, if the server is a proxy, the server has unambiguous evidence that the request could not be met by the next-hop server.

Server Error 5xx :

Response status codes beginning with the digit "5" indicate cases in which the server is aware that it has erred or is incapable of performing the request. Except when responding to a HEAD request, the server SHOULD include an entity containing an explanation of the error situation, and whether it is a temporary or permanent condition. User agents SHOULD display any included entity to the user. These response codes are applicable to any request method.

500 Internal Server Error :

The server encountered an unexpected condition which prevented it from fulfilling the request.

501 Not Implemented :

The server does not support the functionality required to fulfill the request. This is the appropriate response when the server does not recognize the request method and is not capable of supporting it for any resource.

502 Bad Gateway :

The server, while acting as a gateway or proxy, received an invalid response from the upstream server it accessed in attempting to fulfill the request.

503 Service Unavailable :

The server is currently unable to handle the request due to a temporary overloading or maintenance of the server. The implication is that this is a temporary condition which will be alleviated after some delay. If known, the length of the delay MAY be indicated in a Retry-After header. If no Retry-After is given, the client SHOULD handle the response as it would for a 500 response.

Note: The existence of the 503 status code does not imply that a
server must use it when becoming overloaded. Some servers may wish
to simply refuse the connection.

504 Gateway Timeout :

The server, while acting as a gateway or proxy, did not receive a timely response from the upstream server specified by the URI (e.g. HTTP, FTP, LDAP) or some other auxiliary server (e.g. DNS) it needed to access in attempting to complete the request.

Note: Note to implementors: some deployed proxies are known to
return 400 or 500 when DNS lookups time out.

505 HTTP Version Not Supported :

The server does not support, or refuses to support, the HTTP protocol version that was used in the request message. The server is indicating that it is unable or unwilling to complete the request using the same major version as the client, as described in section 3.1, other than with this error message. The response SHOULD contain an entity describing why that version is not supported and what other protocols are supported by that server.