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Created by Fang on January 04, 2012 09:54:05    Last update: January 04, 2012 09:54:05
There are two ways to validate a form with JSF: jsf validation on the page with <f:validate...> tags (for example: <f:validateLength> , <f:validateRegex> , etc.), or JSR303 bean validation. This note is about how to customize messages for JSR303 bean validation. The validation message is specified in the message attribute for each validation annotation type. The mesage attribute is not a literal string, but a string that is interpolated in various ways. For example, the default validation message for AssertFalse is {javax.validation.constraints.AssertFalse.message} , which is replaced with the corresponding string in ValidationMessages.properties (or ValidationMessages_tr.properties , ValidationMessages_es.properties , depending on the locale). This is the contents of ValidationMessages.properties in the hibernate validator reference implementation: javax.validation.constraints.AssertFalse.message =... To customize the messages, just provide the new value in...
Created by alfa on June 02, 2011 15:26:37    Last update: June 02, 2011 15:26:37
While doing some Java reflection code, I noticed the method Class.isSynthetic() , which the JavaDoc says returns " true if and only if this class is a synthetic class as defined by the Java Language Specification". However, there's no definition of "synthetic class" in the JLS ! The only thing that I can find that remotely resembles a definition is in the JVM spec , where it defines the synthetic attribute : "The Synthetic attribute is a fixed-length attribute in the attributes table of ClassFile (§4.1), field_info (§4.5), and method_info (§4.6) structures. A class member that does not appear in the source code must be marked using a Synthetic attribute." By this definition, a default constructor, which does not appear in the source code, should...
Created by Fang on August 23, 2010 22:55:58    Last update: August 24, 2010 15:45:04
The tags XML flow control tags are exactly the same as their Core flow control equivalents, except that the test condition with a boolean EL expression is replaced by the select condition with an XPath expression. In the case of the forEach tag, the items attribute is replaced with the select attribute. In a test condition, the XPath expression is evaluated to a boolean value by the rules of the XPath boolean() function, which converts its argument to a boolean as follows: a number is true if and only if it is neither positive or negative zero nor NaN. a node-set is true if and only if it is non-empty. a string is true if and only if its length is non-zero. an object of...
Created by Dr. Xi on June 11, 2010 23:11:59    Last update: June 11, 2010 23:14:02
Given a simple XML file like this: <?xml version="1.0"?> <root id="1"> ... Calling Document.getElementById returns null (surprisingly!): import java.io.*; import org.w3c.dom.*; impo... In fact the JavaDoc says something along the lines that getElementById returns the Element that has an ID attribute with the given value. An attribute with the name "ID" or "id" is not of type ID unless it is so defined. How is an attribute defined as an ID attribute ? With a DTD or schema. If you are not validating the XML, then the API is useless. So, what to do if you want to find an element for which the attribute named "id" has a given value? Several options were offered in GetElementById Pitfalls . One of them is to...