This is an example of using java.beans.XMLEncoder and java.beans.XMLDecoder to serialize/deserialize Java objects to XML. Java code TestXMLEncoder.java: import java.io.*; import java.beans.XMLEncoder; import java.beans.XMLDecoder; public class TestXMLEncoder { public static void main(String[] args) throws Exception { TestXMLEncoder t = new TestXMLEncoder(); t.testSimpleBean(); t.testCompositeBean(); t.testNoDefaultConstructor(); } private void testSimpleBean() throws Exception { System.out.println("Testing simple bean"); File simpleBeanXml = new File("simplebean.xml"); SimpleBean b = new SimpleBean(); b.setName("Java"); encodeObject(b, simpleBeanXml); SimpleBean b2 = (SimpleBean) decodeObject(simpleBeanXml); System.out.println("Retrieved: " + b2); System.out.println(); } private void testCompositeBean() throws Exception { System.out.println("Testing composite bean"); File compositeBeanXml = new File("compositebean.xml"); CompositeBean b = new CompositeBean(); SimpleBean s = new SimpleBean(); s.setName("Nested"); b.setS(s); encodeObject(b, compositeBeanXml); CompositeBean b2 = (CompositeBean) decodeObject(compositeBeanXml); System.out.println("Retrieved: " + b2); System.out.println(); } private void testNoDefaultConstructor() throws Exception { System.out.println("Testing noDefaultConstructor"); ...

<?xml version="1.0"?> <project name="Ant input task example" default="all" basedir="."> <target name="all" depends="doit,don't"/> <target name="doit" depends="user-input" if="confirmed"> <echo>Task performed</echo> </target> <target name="don't" depends="user-input" unless="confirmed"> <echo>Task NOT performed</echo> </target> <target name="user-input"> <input validargs="y,n" addproperty="user-response"> Do you really want to do this? </input> <condition property="confirmed"> <equals arg1="y" arg2="${user-response}"/> </condition> </target> </project>

This is a Java program to test XPATH expressions with namespace option. It's been tested with JDK1.6. import java.io.FileInputStream; import java.util.Iterator; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.transform.*; import javax.xml.xpath.*; import javax.xml.namespace.NamespaceContext; import org.w3c.dom.*; public class XPathExample { public static void main(String[] args) throws Exception { if (args.length < 2) { usage(); return; } String inputFile = args[0]; String xPathStr = args[1]; // optional namespace spec: xmlns:prefix:URI String nsPrefix = null; String nsUri = null; if ((args.length >= 3) && args[2].startsWith("xmlns:")) { String[] nsDef = args[2].substring("xmlns:".length()).split("="); if (nsDef.length == 2) { nsPrefix = nsDef[0]; nsUri = nsDef[1]; } } // Parse XML to DOM DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance(); dbFactory.setNamespaceAware(true); Document doc = dbFactory .newDocumentBuilder() .parse(new FileInputStream(inputFile)); // Find nodes by XPATH XPathFactory xpFactory = XPathFactory.newInstance(); XPath xpath = ...

Parsing XML in Java is really simple: import java.io.*; import javax.xml.parsers.DocumentBuilderFactory; import org.w3c.dom.Document; public class DOMParserExample { public static void main(String[] args) throws Exception { if (args.length < 1) { System.out.println("Usage: java DOMParserExample <xmlFileName>"); return; } DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); factory.setNamespaceAware(true); InputStream in = new FileInputStream(args[0]); Document doc = factory.newDocumentBuilder().parse(in); in.close(); System.out.println("DOM doc: " + doc); System.out.println("DOM doc class: " + doc.getClass().getName()); } } The parser implementation details are hidden behind the JAXP API. In case you want to know which parser implementation is used, this is what the JavaDoc for DocumentBuilderFactory.newInstance says: Use the javax.xml.parsers.DocumentBuilderFactory system property. Use the properties file " lib/jaxp.properties " in the JRE directory. This configuration file is in standard java.util.Properties format and contains the fully qualified name of the ...

This XML signature validator comes from the Apache XML Security project. It validates the signature according to the core validation processing rules . It does not verify that the key used to generate the signature is a trusted key. You can override the KeySelector class to make sure that the signing key is from a trusted store. import javax.xml.crypto.*; import javax.xml.crypto.dsig.*; import javax.xml.crypto.dom.*; import javax.xml.crypto.dsig.dom.DOMValidateContext; import javax.xml.crypto.dsig.keyinfo.*; import java.io.FileInputStream; import java.security.*; import java.security.interfaces.*; import java.util.Collections; import java.util.Iterator; import java.util.List; import javax.xml.parsers.DocumentBuilderFactory; import org.w3c.dom.Document; import org.w3c.dom.NodeList; /** * This is a simple example of validating an XML * Signature using the JSR 105 API. It assumes the key needed to * validate the signature is contained in a KeyValue KeyInfo. */ public class ValidateXMLSig { // ...

Java SE 6 contains built-in utilities to generate XML signatures. This is an example that generates XML signatures using a Java keystore. It has options to generate signature for the whole document, for an element with a specific ID, or for elements matched by an XPATH expression. The XML document used to test is taken from Getting Started with XML Security : <?xml version="1.0"?> <PatientRecord> <Name>John Doe</Name> <Account id="acct">123456</Account> <Visit date="10pm March 10, 2002"> <Diagnosis>Broken second metacarpal</Diagnosis> </Visit> </PatientRecord> This is the Java code: import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.OutputStream; import java.security.*; import java.security.cert.X509Certificate; import java.util.*; import javax.xml.crypto.*; import javax.xml.crypto.dsig.*; import javax.xml.crypto.dom.*; import javax.xml.crypto.dsig.dom.DOMSignContext; import javax.xml.crypto.dsig.keyinfo.*; import javax.xml.crypto.dsig.spec.*; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.transform.*; import javax.xml.transform.dom.DOMSource; import javax.xml.transform.stream.StreamResult; import javax.xml.xpath.*; import org.w3c.dom.*; /** * Sign XML file. ...

I got this error while starting jboss-5.1.0.GA on Solaris (there were no problems on Windows XP or Linux). 18:20:57,405 ERROR [AbstractKernelController] Error installing to Instantiated: name=AttachmentStore state=Described java.lang.IllegalArgumentException: Wrong arguments. new for target java.lang. reflect.Constructor expected=[java.net.URI] actual=[java.io.File] at org.jboss.reflect.plugins.introspection.ReflectionUtils.handleErrors( ReflectionUtils.java:395) at org.jboss.reflect.plugins.introspection.ReflectionUtils.newInstance(R eflectionUtils.java:153) at org.jboss.reflect.plugins.introspection.ReflectConstructorInfoImpl.ne wInstance(ReflectConstructorInfoImpl.java:106) at org.jboss.joinpoint.plugins.BasicConstructorJoinPoint.dispatch(BasicC onstructorJoinPoint.java:80) at org.jboss.aop.microcontainer.integration.AOPConstructorJoinpoint.crea teTarget(AOPConstructorJoinpoint.java:282) at org.jboss.aop.microcontainer.integration.AOPConstructorJoinpoint.disp atch(AOPConstructorJoinpoint.java:103) at org.jboss.kernel.plugins.dependency.KernelControllerContextAction$Joi npointDispatchWrapper.execute(KernelControllerContextAction.java:241) at org.jboss.kernel.plugins.dependency.ExecutionWrapper.execute(Executio nWrapper.java:47) at org.jboss.kernel.plugins.dependency.KernelControllerContextAction.dis patchExecutionWrapper(KernelControllerContextAction.java:109) It turned out that this was a bug in jboss-5.1.0.GA and was fixed in jboss 6. The fix was to add class="java.io.File" to conf/bootstrap/profile.xml : <bean name="AttachmentStore" class="org.jboss.system.server.profileservice.repository.AbstractAttachmentStore"> <constructor> <parameter class="java.io.File"> <inject bean="BootstrapProfileFactory" property="attachmentStoreRoot"/> </parameter> </constructor> <property name="mainDeployer"> <inject bean="MainDeployer" /> </property> <property name="serializer"> <inject bean="AttachmentsSerializer" /> </property> <property name="persistenceFactory"> <inject bean="PersistenceFactory" /> </property> </bean>

More arguments than format specifiers (place holders) are allowed but not vise versa. public class TestStringFormat { public static void main(String[] args) { System.out.println(String.format("%s", "a", "b", "c")); System.out.println(String.format("%s%s", "a", "b", "c")); System.out.println(String.format("%s%s%s", "a", "b", "c")); System.out.println(String.format("%s%s%s%s", "a", "b", "c")); } }

The + operator which is used in Java to concatenate strings does not work in JSP. In JSP, you simply string them together without the + operator. <!DOCTYPE html> <%@ taglib prefix="c" uri="http://java.sun.com/jstl/core"%> <%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt"%> <%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions"%> <html> <head> <title>Test Page</title> </head> <body> <c:set var="majorVersion" value="1"/> <c:set var="minorVersion" value="03"/> Full version: <c:out value="${majorVersion}.${minorVersion}"/> <br> <c:set var="fullVersion" value="${majorVersion}.${minorVersion}"/> <c:if test="${'1.03' == fullVersion}"> Can't use concatenation directly in test condition, set variable fullVersion first! </c:if> </body> </html>

Given a simple XML file like this: <?xml version="1.0"?> <root id="1"> <node id="12"> <text id="123">Some garbage.</text> </node> </root> Calling Document.getElementById returns null (surprisingly!): import java.io.*; import org.w3c.dom.*; import javax.xml.parsers.*; public class TestGetElementById { public static void main(String[] args) throws Exception { String id = "123"; if (args.length > 0) { id = args[0]; } DocumentBuilderFactory domFactory = DocumentBuilderFactory.newInstance(); System.out.println("Is Validating: " + domFactory.isValidating()); domFactory.setNamespaceAware(true); DocumentBuilder docBuilder = domFactory.newDocumentBuilder(); Document doc = docBuilder.parse("simple.xml"); Node n = doc.getElementById(id); if (n == null) { System.out.println("Failed to find node for id: " + id); } else { System.out.println("Found node: " + n); } } } In fact the JavaDoc says something along the lines that getElementById returns the Element that has an ID attribute with the given value. An ...