ClassUtil.java

package com.zone.weixin4j.util;

import com.zone.weixin4j.exception.WeixinException;

import java.io.*;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.net.JarURLConnection;
import java.net.URISyntaxException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;

/**
 * 对class的获取
 * 
 * @className ClassUtil
 * @author jinyu(foxinmy@gmail.com)
 * @date 2014年10月31日
 * @since JDK 1.6
 * @see
 */
public final class ClassUtil {
	private final static String POINT = ".";
	private final static String CLASS = ".class";

	/**
	 * 获取某个包下所有的class信息
	 * 
	 * @param packageName
	 *            包名
	 * @return
	 */
	public static List<Class<?>> getClasses(String packageName)
			throws WeixinException {
		String packageFileName = packageName.replace(POINT, File.separator);
		URL fullPath = getDefaultClassLoader().getResource(packageFileName);
		String protocol = fullPath.getProtocol();
		if (protocol.equals(ServerToolkits.PROTOCOL_FILE)) {
			try {
				File dir = new File(fullPath.toURI());
				return findClassesByFile(dir, packageName);
			} catch (URISyntaxException e) {
				throw new WeixinException(e);
			}
		} else if (protocol.equals(ServerToolkits.PROTOCOL_JAR)) {
			try {
				return findClassesByJar(
						((JarURLConnection) fullPath.openConnection())
								.getJarFile(),
						packageName);
			} catch (IOException e) {
				throw new WeixinException(e);
			}
		}
		return null;
	}

	/**
	 * 扫描目录下所有的class对象
	 * 
	 * @param dir
	 *            文件目录
	 * @param packageName
	 *            包的全限类名
	 * @return
	 */
	private static List<Class<?>> findClassesByFile(File dir, String packageName) {
		List<Class<?>> classes = new ArrayList<Class<?>>();
		File[] files = dir.listFiles(new FilenameFilter() {
			@Override
			public boolean accept(File file, String name) {
				return file.isDirectory() || file.getName().endsWith(CLASS);
			}
		});
		if (files != null) {
			for (File file : files) {
				if (file.isDirectory()) {
					classes.addAll(findClassesByFile(file, packageName + POINT
							+ file.getName()));
				} else {
					try {
						classes.add(Class.forName(packageName + POINT
								+ file.getName().replace(CLASS, "")));
					} catch (ClassNotFoundException e) {
						;
					}
				}
			}
		}
		return classes;
	}

	/**
	 * 扫描jar包下所有的class对象
	 * 
	 * @param jar
	 *            jar包对象
	 * @param packageName
	 *            包的全限类名
	 * @return
	 */
	private static List<Class<?>> findClassesByJar(JarFile jar,
			String packageName) {
		List<Class<?>> classes = new ArrayList<Class<?>>();
		Enumeration<JarEntry> jarEntries = jar.entries();
		while (jarEntries.hasMoreElements()) {
			JarEntry jarEntry = jarEntries.nextElement();
			if (jarEntry.isDirectory()) {
				continue;
			}
			String className = jarEntry.getName()
					.replace(File.separator, POINT);
			if (!className.startsWith(packageName)
					|| !className.endsWith(CLASS)) {
				continue;
			}
			try {
				classes.add(Class.forName(className.replace(CLASS, "")));
			} catch (ClassNotFoundException e) {
				;
			}
		}
		return classes;
	}

	public static Object deepClone(Object obj) throws WeixinException {
		ByteArrayOutputStream bos = null;
		ObjectOutputStream oos = null;
		ByteArrayInputStream bis = null;
		ObjectInputStream ois = null;
		try {
			bos = new ByteArrayOutputStream();
			oos = new ObjectOutputStream(bos);
			oos.writeObject(obj);
			bis = new ByteArrayInputStream(bos.toByteArray());
			ois = new ObjectInputStream(bis);
			return ois.readObject();
		} catch (IOException e) {
			throw new WeixinException(e);
		} catch (ClassNotFoundException e) {
			throw new WeixinException(e);
		} finally {
			try {
				if (bos != null) {
					bos.close();
				}
				if (oos != null) {
					oos.close();
				}
				if (bis != null) {
					bis.close();
				}
				if (ois != null) {
					ois.close();
				}
			} catch (IOException e) {
				;// ignore
			}
		}
	}

	/**
	 * 获得泛型类型
	 * 
	 * @param object
	 * @return
	 */
	public static Class<?> getGenericType(Class<?> clazz) {
		if(clazz == Object.class){
			return null;
		}
		Type type = clazz.getGenericSuperclass();
		if (type instanceof ParameterizedType) {
			ParameterizedType ptype = ((ParameterizedType) type);
			Type[] args = ptype.getActualTypeArguments();
			return (Class<?>) args[0];
		}
		return getGenericType(clazz.getSuperclass());
	}

	public static ClassLoader getDefaultClassLoader() {
		ClassLoader cl = null;
		try {
			cl = Thread.currentThread().getContextClassLoader();
		} catch (Throwable ex) {
			// Cannot access thread context ClassLoader - falling back...
		}
		if (cl == null) {
			// No thread context class loader -> use class loader of this class.
			cl = ClassUtil.class.getClassLoader();
			if (cl == null) {
				// getClassLoader() returning null indicates the bootstrap
				// ClassLoader
				try {
					cl = ClassLoader.getSystemClassLoader();
				} catch (Throwable ex) {
					// Cannot access system ClassLoader - oh well, maybe the
					// caller can live with null...
				}
			}
		}
		return cl;
	}

	public static void main(String[] args) throws WeixinException {
		System.err.println(getClasses("com.foxinmy.weixin4j.qy.event"));
	}
}