由于Android使用的是DexClassLoader而不是Java程序的AppClassLoader，故在Android中需要使用和Java不同的方式。
相关：Android ClassUtil 方案
1. Java中使用：
package top.littlefogcat.pluginization;
import java.io.File;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import java.util.Objects;
public class ClassUtil {
/**
* 根据传入的根包名，扫描该包下所有类
*
* @param thiz this
* @param rootPackageName 包名
*/
public static List scanClasses(Object thiz, String rootPackageName) {
return scanClasses(thiz.getClass(), rootPackageName);
}
/**
* 根据传入的根包名，扫描该包下所有类
*
* @param thisClass 所在类
* @param rootPackageName 包名
*/
public static List scanClasses(Class thisClass, String rootPackageName) {
return scanClasses(Objects.requireNonNull(thisClass.getClassLoader()), rootPackageName);
}
/**
* 根据传入的根包名和对应classloader，扫描该包下所有类
*/
public static List scanClasses(ClassLoader classLoader, String packageName) {
try {
String packageResource = packageName.replace(".", "/");
URL url = classLoader.getResource(packageResource);
File root = new File(url.toURI());
List classList = new ArrayList<>();
scanClassesInner(root, packageName, classList);
return classList;
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
/**
* 遍历文件夹下所有.class文件，并转换成包名字符串的形式保存在结果List中。
*/
private static void scanClassesInner(File root, String packageName, List result) {
for (File child : Objects.requireNonNull(root.listFiles())) {
String name = child.getName();
if (child.isDirectory()) {
scanClassesInner(child, packageName + "." + name, result);
} else if (name.endsWith(".class")) {
String className = packageName + "." + name.replace(".class", "");
result.add(className);
}
}
}
}
2. Android 中使用：
package com.alibaba.android.arouter.utils;
// Copy from galaxy sdk ${com.alibaba.android.galaxy.utils.ClassUtils}
import android.content.Context;
import android.content.SharedPreferences;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.os.Build;
import android.util.Log;
import com.alibaba.android.arouter.launcher.ARouter;
import com.alibaba.android.arouter.thread.DefaultPoolExecutor;
import java.io.File;
import java.io.IOException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Enumeration;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.concurrent.CountDownLatch;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import dalvik.system.DexFile;
/**
* Scanner, find out class with any conditions, copy from google source code.
*
* @author 正纬 Contact me.
* @version 1.0
* @since 16/6/27 下午10:58
*/
public class ClassUtils {
private static final String EXTRACTED_NAME_EXT = ".classes";
private static final String EXTRACTED_SUFFIX = ".zip";
private static final String SECONDARY_FOLDER_NAME = "code_cache" + File.separator + "secondary-dexes";
private static final String PREFS_FILE = "multidex.version";
private static final String KEY_DEX_NUMBER = "dex.number";
private static final int VM_WITH_MULTIDEX_VERSION_MAJOR = 2;
private static final int VM_WITH_MULTIDEX_VERSION_MINOR = 1;
private static SharedPreferences getMultiDexPreferences(Context context) {
return context.getSharedPreferences(PREFS_FILE, Build.VERSION.SDK_INT < Build.VERSION_CODES.HONEYCOMB ? Context.MODE_PRIVATE : Context.MODE_PRIVATE | Context.MODE_MULTI_PROCESS);
}
/**
* 通过指定包名，扫描包下面包含的所有的ClassName
*
* @param context U know
* @param packageName 包名
* @return 所有class的集合
*/
public static Set getFileNameByPackageName(Context context, final String packageName) throws PackageManager.NameNotFoundException, IOException, InterruptedException {
final Set classNames = new HashSet<>();
List paths = getSourcePaths(context);
final CountDownLatch parserCtl = new CountDownLatch(paths.size());
for (final String path : paths) {
DefaultPoolExecutor.getInstance().execute(new Runnable() {
@Override
public void run() {
DexFile dexfile = null;
try {
if (path.endsWith(EXTRACTED_SUFFIX)) {
//NOT use new DexFile(path), because it will throw "permission error in /data/dalvik-cache"
dexfile = DexFile.loadDex(path, path + ".tmp", 0);
} else {
dexfile = new DexFile(path);
}
Enumeration dexEntries = dexfile.entries();
while (dexEntries.hasMoreElements()) {
String className = dexEntries.nextElement();
if (className.startsWith(packageName)) {
classNames.add(className);
}
}
} catch (Throwable ignore) {
Log.e("ARouter", "Scan map file in dex files made error.", ignore);
} finally {
if (null != dexfile) {
try {
dexfile.close();
} catch (Throwable ignore) {
}
}
parserCtl.countDown();
}
}
});
}
parserCtl.await();
Log.d(Consts.TAG, "Filter " + classNames.size() + " classes by packageName <" + packageName + ">");
return classNames;
}
/**
* get all the dex path
*
* @param context the application context
* @return all the dex path
* @throws PackageManager.NameNotFoundException
* @throws IOException
*/
public static List getSourcePaths(Context context) throws PackageManager.NameNotFoundException, IOException {
ApplicationInfo applicationInfo = context.getPackageManager().getApplicationInfo(context.getPackageName(), 0);
File sourceApk = new File(applicationInfo.sourceDir);
List sourcePaths = new ArrayList<>();
sourcePaths.add(applicationInfo.sourceDir); //add the default apk path
//the prefix of extracted file, ie: test.classes
String extractedFilePrefix = sourceApk.getName() + EXTRACTED_NAME_EXT;
// 如果VM已经支持了MultiDex，就不要去Secondary Folder加载 Classesx.zip了，那里已经么有了
// 通过是否存在sp中的multidex.version是不准确的，因为从低版本升级上来的用户，是包含这个sp配置的
if (!isVMMultidexCapable()) {
//the total dex numbers
int totalDexNumber = getMultiDexPreferences(context).getInt(KEY_DEX_NUMBER, 1);
File dexDir = new File(applicationInfo.dataDir, SECONDARY_FOLDER_NAME);
for (int secondaryNumber = 2; secondaryNumber <= totalDexNumber; secondaryNumber++) {
//for each dex file, ie: test.classes2.zip, test.classes3.zip...
String fileName = extractedFilePrefix + secondaryNumber + EXTRACTED_SUFFIX;
File extractedFile = new File(dexDir, fileName);
if (extractedFile.isFile()) {
sourcePaths.add(extractedFile.getAbsolutePath());
//we ignore the verify zip part
} else {
throw new IOException("Missing extracted secondary dex file '" + extractedFile.getPath() + "'");
}
}
}
if (ARouter.debuggable()) { // Search instant run support only debuggable
sourcePaths.addAll(tryLoadInstantRunDexFile(applicationInfo));
}
return sourcePaths;
}
/**
* Get instant run dex path, used to catch the branch usingApkSplits=false.
*/
private static List tryLoadInstantRunDexFile(ApplicationInfo applicationInfo) {
List instantRunSourcePaths = new ArrayList<>();
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP && null != applicationInfo.splitSourceDirs) {
// add the split apk, normally for InstantRun, and newest version.
instantRunSourcePaths.addAll(Arrays.asList(applicationInfo.splitSourceDirs));
Log.d(Consts.TAG, "Found InstantRun support");
} else {
try {
// This man is reflection from Google instant run sdk, he will tell me where the dex files go.
Class pathsByInstantRun = Class.forName("com.android.tools.fd.runtime.Paths");
Method getDexFileDirectory = pathsByInstantRun.getMethod("getDexFileDirectory", String.class);
String instantRunDexPath = (String) getDexFileDirectory.invoke(null, applicationInfo.packageName);
File instantRunFilePath = new File(instantRunDexPath);
if (instantRunFilePath.exists() && instantRunFilePath.isDirectory()) {
File[] dexFile = instantRunFilePath.listFiles();
for (File file : dexFile) {
if (null != file && file.exists() && file.isFile() && file.getName().endsWith(".dex")) {
instantRunSourcePaths.add(file.getAbsolutePath());
}
}
Log.d(Consts.TAG, "Found InstantRun support");
}
} catch (Exception e) {
Log.e(Consts.TAG, "InstantRun support error, " + e.getMessage());
}
}
return instantRunSourcePaths;
}
/**
* Identifies if the current VM has a native support for multidex, meaning there is no need for
* additional installation by this library.
*
* @return true if the VM handles multidex
*/
private static boolean isVMMultidexCapable() {
boolean isMultidexCapable = false;
String vmName = null;
try {
if (isYunOS()) { // YunOS需要特殊判断
vmName = "'YunOS'";
isMultidexCapable = Integer.valueOf(System.getProperty("ro.build.version.sdk")) >= 21;
} else { // 非YunOS原生Android
vmName = "'Android'";
String versionString = System.getProperty("java.vm.version");
if (versionString != null) {
Matcher matcher = Pattern.compile("(\\d+)\\.(\\d+)(\\.\\d+)?").matcher(versionString);
if (matcher.matches()) {
try {
int major = Integer.parseInt(matcher.group(1));
int minor = Integer.parseInt(matcher.group(2));
isMultidexCapable = (major > VM_WITH_MULTIDEX_VERSION_MAJOR)
|| ((major == VM_WITH_MULTIDEX_VERSION_MAJOR)
&& (minor >= VM_WITH_MULTIDEX_VERSION_MINOR));
} catch (NumberFormatException ignore) {
// let isMultidexCapable be false
}
}
}
}
} catch (Exception ignore) {
}
Log.i(Consts.TAG, "VM with name " + vmName + (isMultidexCapable ? " has multidex support" : " does not have multidex support"));
return isMultidexCapable;
}
/**
* 判断系统是否为YunOS系统
*/
private static boolean isYunOS() {
try {
String version = System.getProperty("ro.yunos.version");
String vmName = System.getProperty("java.vm.name");
return (vmName != null && vmName.toLowerCase().contains("lemur"))
|| (version != null && version.trim().length() > 0);
} catch (Exception ignore) {
return false;
}
}
}