ognl

OGNL stands for Object-Graph Navigation Language; it is an expression language for getting and setting properties of Java objects. You use the same expression for both getting and setting the value of a property.

OGNL started out as a way to set up associations between UI components and controllers using property names. As the desire for more complicated associations grew, Drew Davidson created what he called KVCL, for Key-Value Coding Language, egged on by Luke Blanshard. Luke then reimplemented the language using ANTLR, came up with the new name, and, egged on by Drew, filled it out to its current state.

We pronounce OGNL as a word, like the last syllables of a drunken pronunciation of "orthogonal" or like "ogg-null".

PropertyDescriptor subclass that describes an indexed set of read/write methods to get a property.

This class provides static methods for parsing and interpreting OGNL expressions.

The simplest use of the Ognl class is to get the value of an expression from an object, without extra context or pre-parsing.

 import ognl.Ognl;
 import ognl.OgnlException;
 try {
 result = Ognl.getValue(expression, root);
 } catch (OgnlException ex) {
 // Report error or recover
 }
 

This will parse the expression given and evaluate it against the root object given, returning the result.