When you insert an attribute in JSP: <%@ taglib uri="http://tiles.apache.org/tags-tiles... you must define the attribute in tiles definitions: <definition name="/home" template="/WEB-INF/templa... Otherwise you'll get runtime exception. The ignore attribute, which defaults to false , will suppress the runtime exception when the attribute is not defined in tiles definition: <%@ taglib uri="http://tiles.apache.org/tags-tiles...

Microsoft provides free downloadable Windows images to support IE browser compatibility testing, just google Internet Explorer Application Compatibility VPC Image . These VMs run on Microsoft's Windows Virtual PC . According to MS: You can technically have a base image which never expires although you will never be able to permanently save any changes on these images for longer than 90 days.

You can define environment variables in the Tomcat context.xml file like this: <?xml version="1.0" encoding="UTF-8"?> <Context... which is equivalent to the following in web.xml : <env-entry> <env-entry-name>varName</env-entr... In Java code, the variable can be looked up like this: // import javax.naming.Context; // import javax...

Some methods to search for a substring within a string: To know that a substring indeed exists within a string: boolean found = wholeString.contains(substring); To find where the substring is contained: int index = wholeString.indexOf(substring); If the substring is regex: boolean match = wholeString.matches(".*" + substri... Case insensitive match: convert both whole string and substring to lowercase, then compare. Or, use case insensitive flag for regex. Test code: import java.util.regex.*; public class Stri...

From the Java Language Specification : Because some type information is erased during compilation, not all types are available at run time. Types that are completely available at run time are known as reifiable types . A type is reifiable if and only if one of the following holds: It refers to a non-generic type declaration. It is a parameterized type in which all type arguments are unbounded wildcards. It is a raw type. It is a primitive type. It is an array type whose component type is reifiable. For example: int is a reifiable type (primitive type) List is a reifiable type (raw type) List<?> is a reifiable type (parameterized type with unbound wildcards) List<String> is not a reifiable type (generic type) Class<?> is...

You should drop the generics notation when looking up a method by signature: import java.util.*; import java.lang.reflect.Me... In fact, Class.forName("java.util.List<java.lang.String>") fails with ClassNotFoundException ! However, all information about parameterized types are not lost at runtime. The Java reflection API does provide these methods to get information about parameterized types at runtime: Method.getGenericExceptionTypes Method.getGenericParameterTypes Method.getGenericReturnType for which the non-generic counterparts are: Method.getExceptionTypes Method.getParameterTypes Method.getReturnType

There's no such thing as an immutable byte array in Java. What we are trying to achieve here is to protect the byte array inside the object from which it is being returned. We want to caller to have the contents of the byte array, but not be able to change the contents inside the object. The trick is to return a copy instead of the internal reference: public class ReturnByteArray { public stati...

Read certificate one at a time from BufferedInputStream : // import java.security.cert.*; public void rea... Read all certificates from a file as a collection: public void readCertificates(File f) throws Except...

The XML schema for a contact might look like this: <?xml version="1.0" encoding="UTF-8"?> <schema ... With XML digital signatures , a Signature element is inserted inside the contact element after the contact file is signed. Like this: <?xml version="1.0" encoding="UTF-8" standalone="n... which no longer validates with the original schema. The schema should be updated to (with the addition of digital signature namespace, schema import and Signature ref ): <?xml version="1.0" encoding="UTF-8"?> <schema ...

The String.format() method provides versatile formatting capabilities. This tutorial tries to present these capabilities in a accessible manner. The format string A format string can contain zero, one, or more format specifiers . The general form of a format specifier is: %[argument_index$] [flags] [width] [.precision]co... where things in square brackets are optional, and conversion is a character indicating the conversion to be applied to the corresponding variable value. The only required characters in the format specifier is the percent sign % and the conversion character. A simple example: public static void simpleFormat() { System.out... The Argument index The argument index is specified by a number, terminated by the dollar sign $ . The same argument may be repeated multiple times in a format string. Unindexed...