/*
* Copyright 1999,2004 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.el.util;
import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Array;
import java.lang.reflect.Method;
import java.util.Arrays;
import javax.el.ELException;
import javax.el.MethodNotFoundException;
import javax.el.PropertyNotFoundException;
import org.apache.el.lang.ELSupport;
/**
* Utilities for Managing Serialization and Reflection
*
* @author Jacob Hookom [jacob@hookom.net]
* @version $Change: 181177 $$DateTime: 2001/06/26 08:45:09 $$Author: jhook $
*/
public class ReflectionUtil {
protected static final String[] EMPTY_STRING = new String[0];
protected static final String[] PRIMITIVE_NAMES = new String[] { "boolean",
"byte", "char", "double", "float", "int", "long", "short", "void" };
protected static final Class[] PRIMITIVES = new Class[] { boolean.class,
byte.class, char.class, double.class, float.class, int.class,
long.class, short.class, Void.TYPE };
/**
*
*/
private ReflectionUtil() {
super();
}
public static Class forName(String name) throws ClassNotFoundException {
if (null == name || "".equals(name)) {
return null;
}
Class c = forNamePrimitive(name);
if (c == null) {
if (name.endsWith("[]")) {
String nc = name.substring(0, name.length() - 2);
c = Class.forName(nc, true, Thread.currentThread().getContextClassLoader());
c = Array.newInstance(c, 0).getClass();
} else {
c = Class.forName(name, true, Thread.currentThread().getContextClassLoader());
}
}
return c;
}
protected static Class forNamePrimitive(String name) {
if (name.length() <= 8) {
int p = Arrays.binarySearch(PRIMITIVE_NAMES, name);
if (p >= 0) {
return PRIMITIVES[p];
}
}
return null;
}
/**
* Converts an array of Class names to Class types
* @param s
* @return
* @throws ClassNotFoundException
*/
public static Class[] toTypeArray(String[] s) throws ClassNotFoundException {
if (s == null)
return null;
Class[] c = new Class[s.length];
for (int i = 0; i < s.length; i++) {
c[i] = forName(s[i]);
}
return c;
}
/**
* Converts an array of Class types to Class names
* @param c
* @return
*/
public static String[] toTypeNameArray(Class[] c) {
if (c == null)
return null;
String[] s = new String[c.length];
for (int i = 0; i < c.length; i++) {
s[i] = c[i].getName();
}
return s;
}
/**
* Returns a method based on the criteria
* @param base the object that owns the method
* @param property the name of the method
* @param paramTypes the parameter types to use
* @return the method specified
* @throws MethodNotFoundException
*/
public static Method getMethod(Object base, Object property,
Class[] paramTypes) throws MethodNotFoundException {
if (base == null || property == null) {
throw new MethodNotFoundException(MessageFactory.get(
"error.method.notfound", base, property,
paramString(paramTypes)));
}
String methodName = (property instanceof String) ? (String) property
: property.toString();
Method method = null;
try {
method = base.getClass().getMethod(methodName, paramTypes);
} catch (NoSuchMethodException nsme) {
throw new MethodNotFoundException(MessageFactory.get(
"error.method.notfound", base, property,
paramString(paramTypes)));
}
return method;
}
protected static final String paramString(Class[] types) {
if (types != null) {
StringBuffer sb = new StringBuffer();
for (int i = 0; i < types.length; i++) {
sb.append(types[i].getName()).append(", ");
}
if (sb.length() > 2) {
sb.setLength(sb.length() - 2);
}
return sb.toString();
}
return null;
}
/**
* @param base
* @param property
* @return
* @throws ELException
* @throws PropertyNotFoundException
*/
public static PropertyDescriptor getPropertyDescriptor(Object base,
Object property) throws ELException, PropertyNotFoundException {
String name = ELSupport.coerceToString(property);
PropertyDescriptor p = null;
try {
PropertyDescriptor[] desc = Introspector.getBeanInfo(
base.getClass()).getPropertyDescriptors();
for (int i = 0; i < desc.length; i++) {
if (desc[i].getName().equals(name)) {
return desc[i];
}
}
} catch (IntrospectionException ie) {
throw new ELException(ie);
}
throw new PropertyNotFoundException(MessageFactory.get(
"error.property.notfound", base, name));
}
}