camundafeel.de.odysseus.el.util.SimpleContext Maven / Gradle / Ivy
/*
* Copyright 2006-2009 Odysseus Software GmbH
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package de.odysseus.el.util;
import java.lang.reflect.Method;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import javax.el.ELContext;
import javax.el.ELResolver;
import javax.el.FunctionMapper;
import javax.el.ValueExpression;
import javax.el.VariableMapper;
/**
* Simple context implementation.
*
* @author Christoph Beck
*/
public class SimpleContext extends ELContext {
static class Functions extends FunctionMapper {
Map map = Collections.emptyMap();
@Override
public Method resolveFunction(String prefix, String localName) {
return map.get(prefix + ":" + localName);
}
public void setFunction(String prefix, String localName, Method method) {
if (map.isEmpty()) {
map = new HashMap();
}
map.put(prefix + ":" + localName, method);
}
}
static class Variables extends VariableMapper {
Map map = Collections.emptyMap();
@Override
public ValueExpression resolveVariable(String variable) {
return map.get(variable);
}
@Override
public ValueExpression setVariable(String variable, ValueExpression expression) {
if (map.isEmpty()) {
map = new HashMap();
}
return map.put(variable, expression);
}
}
private Functions functions;
private Variables variables;
private ELResolver resolver;
/**
* Create a context.
*/
public SimpleContext() {
this(null);
}
/**
* Create a context, use the specified resolver.
*/
public SimpleContext(ELResolver resolver) {
this.resolver = resolver;
}
/**
* Define a function.
*/
public void setFunction(String prefix, String localName, Method method) {
if (functions == null) {
functions = new Functions();
}
functions.setFunction(prefix, localName, method);
}
/**
* Define a variable.
*/
public ValueExpression setVariable(String name, ValueExpression expression) {
if (variables == null) {
variables = new Variables();
}
return variables.setVariable(name, expression);
}
/**
* Get our function mapper.
*/
@Override
public FunctionMapper getFunctionMapper() {
if (functions == null) {
functions = new Functions();
}
return functions;
}
/**
* Get our variable mapper.
*/
@Override
public VariableMapper getVariableMapper() {
if (variables == null) {
variables = new Variables();
}
return variables;
}
/**
* Get our resolver. Lazy initialize to a {@link SimpleResolver} if necessary.
*/
@Override
public ELResolver getELResolver() {
if (resolver == null) {
resolver = new SimpleResolver();
}
return resolver;
}
/**
* Set our resolver.
*
* @param resolver
*/
public void setELResolver(ELResolver resolver) {
this.resolver = resolver;
}
}