org.activiti.engine.impl.juel

Class AstNode

java.lang.Object

org.activiti.engine.impl.juel.AstNode

All Implemented Interfaces:

ExpressionNode, Node

Direct Known Subclasses:

AstEval, AstIdentifier, AstMethod, AstProperty, AstRightValue, AstText

public abstract class AstNode
extends Object
implements ExpressionNode

Constructor Summary

Constructors

Constructor and Description
AstNode()

Method Summary

Methods

Modifier and Type	Method and Description
abstract void	appendStructure(StringBuilder builder, Bindings bindings)
abstract Object	eval(Bindings bindings, ELContext context)
String	getStructuralId(Bindings bindings) Get the canonical expression string for this node.
Object	getValue(Bindings bindings, ELContext context, Class<?> type) evaluate and return the (optionally coerced) result.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.activiti.engine.impl.juel.ExpressionNode

getMethodInfo, getType, getValueReference, invoke, isLeftValue, isLiteralText, isMethodInvocation, isReadOnly, setValue

Methods inherited from interface org.activiti.engine.impl.juel.Node

getCardinality, getChild

Constructor Detail

AstNode

public AstNode()

Method Detail

getValue

public final Object getValue(Bindings bindings,
              ELContext context,
              Class<?> type)

evaluate and return the (optionally coerced) result.

Specified by:

getValue in interface ExpressionNode

Parameters:

bindings - bindings containing variables and functions

context - evaluation context

type - result type

Returns:

evaluated node, coerced to the expected type

appendStructure

public abstract void appendStructure(StringBuilder builder,
                   Bindings bindings)

eval

public abstract Object eval(Bindings bindings,
          ELContext context)

getStructuralId

public final String getStructuralId(Bindings bindings)

Description copied from interface: ExpressionNode

Get the canonical expression string for this node. Variable and funtion names will be replaced in a way such that two expression nodes that have the same node structure and bindings will also answer the same value here.

For example, "${foo:bar()+2*foobar}" may lead to "${<fn>() + 2 * <var>}" if foobar is a bound variable. Otherwise, the structural id would be "${<fn>() + 2 * foobar}".

If the bindings is null, the full canonical subexpression is returned.

Specified by:

getStructuralId in interface ExpressionNode