org.apache.jasper.runtime.ProtectedFunctionMapper Maven / Gradle / Ivy
/*
* Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
* Copyright 2004 The Apache Software Foundation
*
* 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 org.apache.jasper.runtime;
import java.util.HashMap;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.security.PrivilegedExceptionAction;
import java.security.PrivilegedActionException;
import java.lang.reflect.Method;
import javax.el.FunctionMapper;
import org.apache.jasper.security.SecurityUtil;
/**
* Maps EL functions to their Java method counterparts. Keeps the
* actual Method objects protected so that JSP pages can't indirectly
* do reflection.
*
* @author Mark Roth
* @author Kin-man Chung
*/
public final class ProtectedFunctionMapper extends FunctionMapper {
/**
* Maps "prefix:name" to java.lang.Method objects.
*/
private HashMap fnmap = null;
/**
* If there is only one function in the map, this is the Method for it.
*/
private Method theMethod = null;
/**
* Constructor has protected access.
*/
private ProtectedFunctionMapper() {
}
/**
* Generated Servlet and Tag Handler implementations call this
* method to retrieve an instance of the ProtectedFunctionMapper.
* This is necessary since generated code does not have access to
* create instances of classes in this package.
*
* @return A new protected function mapper.
*/
public static ProtectedFunctionMapper getInstance() {
ProtectedFunctionMapper funcMapper;
if (SecurityUtil.isPackageProtectionEnabled()) {
funcMapper = AccessController.doPrivileged(
new PrivilegedAction() {
public ProtectedFunctionMapper run() {
return new ProtectedFunctionMapper();
}
} );
} else {
funcMapper = new ProtectedFunctionMapper();
}
funcMapper.fnmap = new java.util.HashMap();
return funcMapper;
}
/**
* Stores a mapping from the given EL function prefix and name to
* the given Java method.
*
* @param fnQName The EL function qualified name (including prefix)
* @param c The class containing the Java method
* @param methodName The name of the Java method
* @param args The arguments of the Java method
* @throws RuntimeException if no method with the given signature
* could be found.
*/
public void mapFunction(String fnQName, final Class c,
final String methodName, final Class[] args )
{
java.lang.reflect.Method method;
if (SecurityUtil.isPackageProtectionEnabled()){
try{
method = AccessController.doPrivileged(
new PrivilegedExceptionAction(){
public Method run() throws Exception{
return c.getDeclaredMethod(methodName, args);
}
});
} catch (PrivilegedActionException ex){
throw new RuntimeException(
"Invalid function mapping - no such method: "
+ ex.getException().getMessage());
}
} else {
try {
method = c.getDeclaredMethod(methodName, args);
} catch( NoSuchMethodException e ) {
throw new RuntimeException(
"Invalid function mapping - no such method: "
+ e.getMessage());
}
}
this.fnmap.put(fnQName, method );
}
/**
* Creates an instance for this class, and stores the Method for
* the given EL function prefix and name. This method is used for
* the case when there is only one function in the EL expression.
*
* @param fnQName The EL function qualified name (including prefix)
* @param c The class containing the Java method
* @param methodName The name of the Java method
* @param args The arguments of the Java method
* @throws RuntimeException if no method with the given signature
* could be found.
*/
public static ProtectedFunctionMapper getMapForFunction(
String fnQName, final Class c,
final String methodName, final Class[] args )
{
java.lang.reflect.Method method;
ProtectedFunctionMapper funcMapper;
if (SecurityUtil.isPackageProtectionEnabled()){
funcMapper = AccessController.doPrivileged(
new PrivilegedAction(){
public ProtectedFunctionMapper run() {
return new ProtectedFunctionMapper();
}
});
try{
method = AccessController.doPrivileged(
new PrivilegedExceptionAction(){
public Method run() throws Exception{
return c.getDeclaredMethod(methodName, args);
}
});
} catch (PrivilegedActionException ex){
throw new RuntimeException(
"Invalid function mapping - no such method: "
+ ex.getException().getMessage());
}
} else {
funcMapper = new ProtectedFunctionMapper();
try {
method = c.getDeclaredMethod(methodName, args);
} catch( NoSuchMethodException e ) {
throw new RuntimeException(
"Invalid function mapping - no such method: "
+ e.getMessage());
}
}
funcMapper.theMethod = method;
return funcMapper;
}
/**
* Resolves the specified local name and prefix into a Java.lang.Method.
* Returns null if the prefix and local name are not found.
*
* @param prefix the prefix of the function
* @param localName the short name of the function
* @return the result of the method mapping. Null means no entry found.
*/
public Method resolveFunction(String prefix, String localName) {
if (this.fnmap != null) {
return this.fnmap.get(prefix + ":" + localName);
}
return theMethod;
}
}