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Android 缓存清理实现工具类

Android工具缓存 实现 清理
2023-09-11 14:15:13 时间

        所有Android设备都有两个文件存储区域:内部存储空间(internal Storage)和外部存储空间(external Storage)。这些名称是在Android早期确定的,那时候大部分设备都提供内置的非易失性内存(内部存储空间)以及可移动存储媒介(如,Micro SD卡,提供外部存储空间)。现在,很多设备将永久性存储空间划分为单独的“内部”和“外部”分区。因此,即使没有可移动存储媒介,这两种存储空间也始终存在,并且无论外部存储空间是否可移动,这两种存储空间的API行为在Android系统上都是相同的。

 可参考:Android内、外存储分区&常用存储目录详解(Android Q)_大渔歌_的博客-CSDN博客

以下为两个清除应用缓存的工具类

1.DataCleanManager.java

/** * 本应用数据清除管理器 */
public class DataCleanManager {
    private static final String TAG = "DataCleanManager";
    public static String getTotalCacheSize(Context context) throws Exception {
        long cacheSize = getFolderSize(context.getCacheDir());
        Log.v(TAG,"cacheSize=="+cacheSize);
        if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
            cacheSize += getFolderSize(context.getExternalCacheDir());
            Log.v(TAG,"cacheSize2=="+ getFolderSize(context.getExternalCacheDir()));
        }
        return getFormatSize(cacheSize);
    }

    //删除内外缓存
    public static void clearAllCache(Context context) {
        deleteDir(context.getCacheDir());
        if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
            deleteDir(context.getExternalCacheDir());
        }
    }
    private static boolean deleteDir(File dir) {
        if (dir != null && dir.isDirectory()) {
            String[] children = dir.list();
            for (int i = 0; i < children.length; i++) {
                boolean success = deleteDir(new File(dir, children[i]));
                if (!success) {
                    return false;
                }
            }
        }
        return dir.delete();
    }

    // 获取文件
    //Context.getExternalFilesDir() --> SDCard/Android/data/你的应用的包名/files/ 目录,一般放一些长时间保存的数据
    //Context.getExternalCacheDir() --> SDCard/Android/data/你的应用包名/cache/目录,一般存放临时缓存数据
    public static long getFolderSize(File file) throws Exception {
        long size = 0;
        try {
            File[] fileList = file.listFiles();
            for (int i = 0; i < fileList.length; i++) {
                // 如果下面还有文件
                if (fileList[i].isDirectory()) {
                    size = size + getFolderSize(fileList[i]);
                } else {
                    size = size + fileList[i].length();
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return size;
    }

    /**
     * 格式化单位
     *
     * @param size
     * @return
     */
    public static String getFormatSize(long size) {
        Log.v(TAG,"size=="+size);
        double kiloByte = size/1024;
        if (kiloByte < 1) {
            return size/1024 + "kB";
        }
        double megaByte = kiloByte/1024;
        if (megaByte < 1) {
            BigDecimal result1 = new BigDecimal(Double.toString(kiloByte));
            return result1.setScale(1, BigDecimal.ROUND_HALF_UP)
                    .toPlainString() + "KB";
        }
        double gigaByte = megaByte / 1024;
        if (gigaByte < 1) {
            BigDecimal result2 = new BigDecimal(Double.toString(megaByte));
            return result2.setScale(1, BigDecimal.ROUND_HALF_UP)
                    .toPlainString() + "MB";
        }
        double teraBytes = gigaByte / 1024;
        if (teraBytes < 1) {
            BigDecimal result3 = new BigDecimal(Double.toString(gigaByte));
            return result3.setScale(2, BigDecimal.ROUND_HALF_UP)
                    .toPlainString() + "GB";
        }
        BigDecimal result4 = new BigDecimal(teraBytes);
        return result4.setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString()
                + "TB";
    }

}
  • 获取缓存
  String resultCache = DataCleanManager.getTotalCacheSize(context);
  • 删除缓存
DataCleanManager.clearAllCache(context);

2. DateclearManager.java

public class DateclearManager {

    /** * 清除本应用内部缓存(/data/data/com.xxx.xxx/cache) * * @param context */
    public static void cleanInternalCache(Context context) {
        deleteFilesByDirectory(context.getCacheDir());
    }

    /** * 清除本应用所有数据库(/data/data/com.xxx.xxx/databases) * * @param context */
    public static void cleanDatabases(Context context) {
        deleteFilesByDirectory(new File("/data/data/"
                + context.getPackageName() + "/databases"));
    }

    /**
     * * 清除本应用SharedPreference(/data/data/com.xxx.xxx/shared_prefs) * * @param
     * context
     */
    public static void cleanSharedPreference(Context context) {
        deleteFilesByDirectory(new File("/data/data/"
                + context.getPackageName() + "/shared_prefs"));
    }

    /** * 按名字清除本应用数据库 * * @param context * @param dbName */
    public static void cleanDatabaseByName(Context context, String dbName) {
        context.deleteDatabase(dbName);
    }

    /** * 清除/data/data/com.xxx.xxx/files下的内容 * * @param context */
    public static void cleanFiles(Context context) {
        deleteFilesByDirectory(context.getFilesDir());
    }

    /**
     * * 清除外部cache下的内容(/mnt/sdcard/android/data/com.xxx.xxx/cache) * * @param
     * context
     */
    public static void cleanExternalCache(Context context) {
        if (Environment.getExternalStorageState().equals(
                Environment.MEDIA_MOUNTED)) {
            deleteFilesByDirectory(context.getExternalCacheDir());
        }
    }

    /** * 清除自定义路径下的文件,使用需小心,请不要误删。而且只支持目录下的文件删除 * * @param filePath */
    public static void cleanCustomCache(String filePath) {
        deleteFilesByDirectory(new File(filePath));
    }

    /** * 清除本应用所有的数据 * * @param context * @param filepath */
    public static void cleanApplicationData(Context context, String... filepath) {
        cleanInternalCache(context);
        cleanExternalCache(context);
        cleanDatabases(context);
        cleanSharedPreference(context);
        cleanFiles(context);
        for (String filePath : filepath) {
            cleanCustomCache(filePath);
        }
    }

    /**
     *删除方法 这里只会删除某个文件夹下的文件,如果传入的directory是个文件,将不做处理
     *  @param directory
     */
    private static void deleteFilesByDirectory(File directory) {
        if (directory != null && directory.exists() && directory.isDirectory()) {
            for (File item : directory.listFiles()) {
                item.delete();
            }
        }
    }


    /**
     * 获得所有缓存数据的大小
     * @param context
     * @return
     * @throws Exception
     */
    public static String getTotalCacheSize(Context context) throws Exception {
        long cacheSize = getFolderSize(context.getCacheDir());
        if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
            cacheSize += getFolderSize(context.getExternalCacheDir());
        }
        return getFormatSize(cacheSize);
    }

    //清空缓存
    public static void clearAllCache(Context context) {
        deleteDir(context.getCacheDir());
        if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
            deleteDir(context.getExternalCacheDir());
        }
    }

    //删除文件
    private static boolean deleteDir(File dir) {
        if (dir != null && dir.isDirectory()) {
            String[] children = dir.list();
            for (int i = 0; i < children.length; i++) {
                boolean success = deleteDir(new File(dir, children[i]));
                if (!success) {
                    return false;
                }
            }
        }
        return dir.delete();
    }

    // 获取文件大小
    //Context.getExternalFilesDir() --> SDCard/Android/data/你的应用的包名/files/ 目录,一般放一些长时间保存的数据
    //Context.getExternalCacheDir() --> SDCard/Android/data/你的应用包名/cache/目录,一般存放临时缓存数据
    public static long getFolderSize(File file) throws Exception {
        long size = 0;
        try {
            File[] fileList = file.listFiles();
            for (int i = 0; i < fileList.length; i++) {
                // 如果下面还有文件
                if (fileList[i].isDirectory()) {
                    size = size + getFolderSize(fileList[i]);
                } else {
                    size = size + fileList[i].length();
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return size;
    }

    /**
     * 格式化文件的单位  转化文件单位
     * @param size
     * @return
     */
    public static String getFormatSize(double size) {
        double kiloByte = size / 1024;
        if (kiloByte < 1) {
//            return size + "Byte";
            return "0K";
        }

        double megaByte = kiloByte / 1024;
        if (megaByte < 1) {
            BigDecimal result1 = new BigDecimal(Double.toString(kiloByte));
            return result1.setScale(2, BigDecimal.ROUND_HALF_UP)
                    .toPlainString() + "KB";
        }

        double gigaByte = megaByte / 1024;
        if (gigaByte < 1) {
            BigDecimal result2 = new BigDecimal(Double.toString(megaByte));
            return result2.setScale(2, BigDecimal.ROUND_HALF_UP)
                    .toPlainString() + "MB";
        }

        double teraBytes = gigaByte / 1024;
        if (teraBytes < 1) {
            BigDecimal result3 = new BigDecimal(Double.toString(gigaByte));
            return result3.setScale(2, BigDecimal.ROUND_HALF_UP)
                    .toPlainString() + "GB";
        }
        BigDecimal result4 = new BigDecimal(teraBytes);
        return result4.setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString()
                + "TB";
    }

}