Mega Code Archive
Find a setter method for the give objects property and try to call it
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/*
* Copyright 2008 Ayman Al-Sairafi ayman.alsairafi@gmail.com
*
* 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 jsyntaxpane.util;
import java.io.File;
import java.io.IOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Member;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.net.URL;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
* Reflection Utility methods
*
* @author Ayman Al-Sairafi
*/
public class ReflectUtils {
/**
* Find a setter method for the give object's property and try to call it.
* No exceptions are thrown. You typically call this method because either
* you are sure no exceptions will be thrown, or to silently ignore
* any that may be thrown.
* This will also find a setter that accepts an interface that the value
* implements.
* <b>This is still not very effcient and should only be called if
* performance is not of an issue.</b>
* You can check the return value to see if the call was seuccessful or
* not.
* @param obj Object to receive the call
* @param property property name (without set. First letter will be
* capitalized)
* @param value Value of the property.
* @return
*/
public static boolean callSetter(Object obj, String property, Object value) {
String key = String.format("%s.%s(%s)", obj.getClass().getName(),
property, value.getClass().getName());
Method m = null;
boolean result = false;
if(!SETTERS_MAP.containsKey(key)) {
m = findMethod(obj, property, value);
SETTERS_MAP.put(key, m);
} else {
m = SETTERS_MAP.get(key);
}
if(m != null) {
try {
m.invoke(obj, value);
result = true;
} catch (IllegalAccessException ex) {
Logger.getLogger(ReflectUtils.class.getName()).log(Level.SEVERE, null, ex);
} catch (IllegalArgumentException ex) {
Logger.getLogger(ReflectUtils.class.getName()).log(Level.SEVERE, null, ex);
} catch (InvocationTargetException ex) {
Logger.getLogger(ReflectUtils.class.getName()).log(Level.SEVERE, null, ex);
}
}
return result;
}
/**
* Scans all classes accessible from the context class loader which belong to the given package and subpackages.
*
* @param packageName The base package
* @return The classes
* @throws ClassNotFoundException
* @throws IOException
*/
private static Class[] getClasses(String packageName)
throws ClassNotFoundException, IOException {
// ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
ClassLoader classLoader = ClassLoader.getSystemClassLoader();
assert classLoader != null;
String path = packageName.replace('.', '/');
Enumeration<URL> resources = classLoader.getResources(path);
List<File> dirs = new ArrayList<File>();
while (resources.hasMoreElements()) {
URL resource = resources.nextElement();
dirs.add(new File(resource.getFile()));
}
ArrayList<Class> classes = new ArrayList<Class>();
for (File directory : dirs) {
classes.addAll(findClasses(directory, packageName));
}
return classes.toArray(new Class[classes.size()]);
}
/**
* Recursive method used to find all classes in a given directory and subdirs.
*
* @param directory The base directory
* @param packageName The package name for classes found inside the base directory
* @return The classes
* @throws ClassNotFoundException
*/
private static List<Class> findClasses(File directory, String packageName) throws ClassNotFoundException {
List<Class> classes = new ArrayList<Class>();
if (!directory.exists()) {
return classes;
}
File[] files = directory.listFiles();
for (File file : files) {
if (file.isDirectory()) {
assert !file.getName().contains(".");
classes.addAll(findClasses(file, packageName + "." + file.getName()));
} else if (file.getName().endsWith(".class")) {
classes.add(Class.forName(packageName + '.' + file.getName().substring(0, file.getName().length() - 6)));
}
}
return classes;
}
private static synchronized Method findMethod(Object obj,
String property, Object value) {
Method m = null;
Class<?> theClass = obj.getClass();
String setter = String.format("set%C%s",
property.charAt(0), property.substring(1));
Class paramType = value.getClass();
while (paramType != null) {
try {
m = theClass.getMethod(setter, paramType);
return m;
} catch (NoSuchMethodException ex) {
// try on the interfaces of this class
for (Class iface : paramType.getInterfaces()) {
try {
m = theClass.getMethod(setter, iface);
return m;
} catch (NoSuchMethodException ex1) {
}
}
paramType = paramType.getSuperclass();
}
}
return m;
}
public static final List<String> DEFAULT_PACKAGES = new ArrayList<String>(3);
static {
DEFAULT_PACKAGES.add("java.lang");
DEFAULT_PACKAGES.add("java.util");
DEFAULT_PACKAGES.add("jsyntaxpane");
}
/**
* To speed up find setter methods, this map will be used.
* The Key String will be of the format objectClass.property(valueclass)
* Where:
* objectClass = obj.getClass().getName
* property = property (as passed in to callSetter), before set is appended
* valueCLass = value.getClass().getName()
* The Method will be either the method, or null if a search was not and no
* method is found.
*/
private static HashMap<String, Method> SETTERS_MAP = new HashMap<String, Method>();
}
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