Read all the classes in the class path.

ClassUtil.java

package com.khotyn.test;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;

/**
 * A utility that can read all the classes in the class path.
 * 
 * @author khotyn 2011-11-29 上午9:34:25
 */
public class ClassUtil {

    /**
     * Get all the classes that defined under the class path.
     * 
     * @return
     * @throws IOException
     */
    public static List<String> getClassesFromClassPath() throws IOException {
        String[] classPathes = System.getProperty("java.class.path").split(":");
        List<String> result = new ArrayList<String>();

        for (String classPath : classPathes) {
            File classPathFile = new File(classPath);

            if (classPathFile.isDirectory()) {
                List<String> children = getSubFiles(classPathFile);

                for (String child : children) {
                    String pathRelativeToClassPath = child.substring(classPathFile.getAbsolutePath().length() + 1);

                    if (pathRelativeToClassPath.endsWith(".class")) {
                        result.add(pathRelativeToClassPath.replace('/', '.').replace(".class", ""));
                    }
                }

            } else if (classPath.endsWith("jar")) {
                JarFile classJar = new JarFile(classPathFile);
                Enumeration<JarEntry> classEntries = classJar.entries();

                while (classEntries.hasMoreElements()) {
                    JarEntry classEntry = classEntries.nextElement();

                    if (classEntry.getName().endsWith(".class")) {
                        result.add(classEntry.getName().replace("/", ".").replace(".class", ""));
                    }
                }
            }
        }

        return result;
    }

    private static List<String> getSubFiles(File orgFile) {
        List<String> subFiles = new ArrayList<String>();

        if (orgFile.isDirectory()) {
            File[] files = orgFile.listFiles();

            for (File subFile : files) {
                if (subFile.isDirectory()) {
                    subFiles.addAll(getSubFiles(subFile));
                } else {
                    subFiles.add(subFile.getAbsolutePath());
                }
            }
        }

        return subFiles;
    }
}