开发中经常用到的工具类

在开发中，我们经常会用到一些开发工具类，比如网络请求（当然，网络请求有成熟的框架，在一些大的项目中确实有可用之处，但是在小项目中用框架的话就有点“杀鸡用了杀牛刀了”），所以我们会写一些功能少的框架，再比如说在开发中我们会为了开发的简单，代码易修改和易添加，对代码的重构有很大的帮助

1、在mvc / map 这种开发模式中，model层也就是数据层，一般小的项目中，在android中不会有数据库在前端出现，这时我们为了将数据层归纳的详细，一般会将要使用到的需要保存在sharedpreferences等，和数据层联系起来，比如：在res/values 下建立config.xml文件 将要保存的字段写在里面

<?xml version="1.0" encoding="utf-8"?><resources>    <string name="client_login_sessionToken">client_login_sessionToken</string><!--存储token值--></resources>

然后在自己的工具类中 创建字段 并且创建读取该文件的方法

public static final String CLIENT_LOGIN_SESSIONTOKEN = "client_login_sessionToken";/** * 读取配置文件 * @param name * @return */public static String getConfigString(String name){    int config = mContext.getResources().getIdentifier(name, "config", "com.kerust.client");    return mContext.getResources().getString(config);}

在加上写的保存sharedpreferences的工具类

public static void put(Context context, String key, Object object) {   SharedPreferences sp = context.getSharedPreferences(FILE_NAME,         Context.MODE_PRIVATE);   SharedPreferences.Editor editor = sp.edit();   if (object instanceof String)   {      editor.putString(key, (String) object);   } else if (object instanceof Integer)   {      editor.putInt(key, (Integer) object);   } else if (object instanceof Boolean)   {      editor.putBoolean(key, (Boolean) object);   } else if (object instanceof Float)   {      editor.putFloat(key, (Float) object);   } else if (object instanceof Long)   {      editor.putLong(key, (Long) object);   } else   {      editor.putString(key, object.toString());   }   SharedPreferencesCompat.apply(editor);}

在要使用的地方

SPUtils.put(mContext, SettingsInfo.getConfigString( //将token保存到本地        SettingsInfo.CLIENT_LOGIN_SESSIONTOKEN),sessionToken);

这样将自己要保存的数据保存起来

好了，这只是我自己在开发的过程中的自己的编程习惯

接下来说几个会经常用得到的工具类

1、保存sharedpreferences的工具类

/** * 保存在手机里面的文件名 */public static final String FILE_NAME = "Launcher_client_share_data";/** * 保存数据的方法，

我们需要拿到保存数据的具体类型，

然后根据类型调用不同的保存方法 *  * @param context * @param key * @param object */public static void put(Context context, String key, Object object) {   SharedPreferences sp = context.getSharedPreferences(FILE_NAME,         Context.MODE_PRIVATE);   SharedPreferences.Editor editor = sp.edit();   if (object instanceof String)   {      editor.putString(key, (String) object);   } else if (object instanceof Integer)   {      editor.putInt(key, (Integer) object);   } else if (object instanceof Boolean)   {      editor.putBoolean(key, (Boolean) object);   } else if (object instanceof Float)   {      editor.putFloat(key, (Float) object);   } else if (object instanceof Long)   {      editor.putLong(key, (Long) object);   } else   {      editor.putString(key, object.toString());   }   SharedPreferencesCompat.apply(editor);}/** * 得到保存数据的方法，

我们根据默认值得到保存的数据的具体类型，然后调用相对于的方法获取值 * 

 * @param context * @param key * @param defaultObject * @return */public static Object get(Context context, String key, Object defaultObject){   SharedPreferences sp = context.getSharedPreferences(FILE_NAME,         Context.MODE_PRIVATE);   if (defaultObject instanceof String)   {      return sp.getString(key, (String) defaultObject);   } else if (defaultObject instanceof Integer)   {      return sp.getInt(key, (Integer) defaultObject);   } else if (defaultObject instanceof Boolean)   {      return sp.getBoolean(key, (Boolean) defaultObject);   } else if (defaultObject instanceof Float)   {      return sp.getFloat(key, (Float) defaultObject);   } else if (defaultObject instanceof Long)   {      return sp.getLong(key, (Long) defaultObject);   }   return null;

只是常用的保存和取值

2、加密算法

/** * DES算法，加密 * * @param data 待加密字符串 * @param key  需要加密的业务类型 * @return 加密后的字节数组，一般结合Base64编码使用 * @throws Exception */public static String encode(String key, String data) {    if (data == null)        return null;    try {        String value = SettingInfo.getDESValue(key);        DESKeySpec dks = new DESKeySpec(value.getBytes());        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");        // key的长度不能够小于8位字节        Key secretKey = keyFactory.generateSecret(dks);        Cipher cipher = Cipher.getInstance(ALGORITHM_DES);        IvParameterSpec iv = new IvParameterSpec("12345678".getBytes());        AlgorithmParameterSpec paramSpec = iv;        cipher.init(Cipher.ENCRYPT_MODE, secretKey, paramSpec);        byte[] bytes = cipher.doFinal(data.getBytes());        return byte2String(bytes);    } catch (Exception e) {        e.printStackTrace();        return data;    }}/** * DES算法，解密 * * @param data 待解密字符串 * @param key  需要解密的业务类型 * @return 解密后的字节数组 * @throws Exception 异常 */public static String decode(String key, String data) {    if (data == null)        return null;    try {        String value = SettingInfo.getDESValue(key);        DESKeySpec dks = new DESKeySpec(value.getBytes());        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");        // key的长度不能够小于8位字节        Key secretKey = keyFactory.generateSecret(dks);        Cipher cipher = Cipher.getInstance(ALGORITHM_DES);        IvParameterSpec iv = new IvParameterSpec("12345678".getBytes());        AlgorithmParameterSpec paramSpec = iv;        cipher.init(Cipher.DECRYPT_MODE, secretKey, paramSpec);        return new String(cipher.doFinal(byte2hex(data.getBytes())));    } catch (Exception e) {        e.printStackTrace();        return data;    }}/** * 二行制转字符串 * * @param b * @return String */private static String byte2String(byte[] b) {    StringBuilder hs = new StringBuilder();    String stmp;    for (int n = 0; b != null && n < b.length; n++) {        stmp = Integer.toHexString(b[n] & 0XFF);        if (stmp.length() == 1)            hs.append('0');        hs.append(stmp);    }    return hs.toString().toUpperCase(Locale.CHINA);}/** * 二进制转化成16进制 * * @param b * @return byte */private static byte[] byte2hex(byte[] b) {    if ((b.length % 2) != 0)        throw new IllegalArgumentException();    byte[] b2 = new byte[b.length / 2];    for (int n = 0; n < b.length; n += 2) {        String item = new String(b, n, 2);        b2[n / 2] = (byte) Integer.parseInt(item, 16);    }    return b2;}/** * md5文件加密的方式 * * @param file * @return md5加密的返回加密后的值 * @throws IOException */public static String md5(File file) throws IOException {    MessageDigest messagedigest = null;    FileInputStream in = null;    FileChannel ch = null;    byte[] encodeBytes = null;    try {        messagedigest = MessageDigest.getInstance("MD5");        in = new FileInputStream(file);        ch = in.getChannel();        MappedByteBuffer byteBuffer = ch.map(FileChannel.MapMode.READ_ONLY, 0, file.length());        messagedigest.update(byteBuffer);        encodeBytes = messagedigest.digest();    } catch (NoSuchAlgorithmException neverHappened) {        throw new RuntimeException(neverHappened);    } finally {        closeQuietly(in);        closeQuietly(ch);    }    return toHexString(encodeBytes);}/** * MD5 字符串的加密方式 * * @param string * @return 加密后的字符串 */public static String md5(String string) {    byte[] encodeBytes = null;    try {        encodeBytes = MessageDigest.getInstance("MD5").digest(string.getBytes("UTF-8"));    } catch (NoSuchAlgorithmException neverHappened) {        throw new RuntimeException(neverHappened);    } catch (UnsupportedEncodingException neverHappened) {        throw new RuntimeException(neverHappened);    }    return toHexString(encodeBytes);}public static void closeQuietly(Closeable closeable) {    if (closeable != null) {        try {            closeable.close();        } catch (Throwable ignored) {            Log.d(ignored.getMessage(), ignored + "");        }    }}private static final char hexDigits[] =        {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};public static String toHexString(byte[] bytes) {    if (bytes == null) return "";    StringBuilder hex = new StringBuilder(bytes.length * 2);    for (byte b : bytes) {        hex.append(hexDigits[(b >> 4) & 0x0F]);        hex.append(hexDigits[b & 0x0F]);    }    return hex.toString();}

3、SD卡保存

/** * 判断SDCard是否可用 * * @return */public static boolean isSDCardEnable(){   return Environment.getExternalStorageState().equals(         Environment.MEDIA_MOUNTED);}/** * 获取SD卡路径 * * @return */public static String getSDCardPath(){   return Environment.getExternalStorageDirectory().getAbsolutePath()         + File.separator;}/** * 获取SD卡的剩余容量 单位byte * * @return */public static long getSDCardAllSize(){   if (isSDCardEnable())   {      StatFs stat = new StatFs(getSDCardPath());      // 获取空闲的数据块的数量      long availableBlocks = (long) stat.getAvailableBlocks() - 4;      // 获取单个数据块的大小（byte）      long freeBlocks = stat.getAvailableBlocks();      return freeBlocks * availableBlocks;   }   return 0;}/** * 获取指定路径所在空间的剩余可用容量字节数，单位byte * * @param filePath * @return 容量字节 SDCard可用空间，内部存储可用空间 */public static long getFreeBytes(String filePath){   // 如果是sd卡的下的路径，则获取sd卡可用容量   if (filePath.startsWith(getSDCardPath()))   {      filePath = getSDCardPath();   } else   {// 如果是内部存储的路径，则获取内存存储的可用容量      filePath = Environment.getDataDirectory().getAbsolutePath();   }   StatFs stat = new StatFs(filePath);   long availableBlocks = (long) stat.getAvailableBlocks() - 4;   return stat.getBlockSize() * availableBlocks;}/** * 获取系统存储路径 * * @return */public static String getRootDirectoryPath(){   return Environment.getRootDirectory().getAbsolutePath();}

4、File操作类

/** * read file * * @param filePath * @return if file not exist, return null, else return content of file * @throws RuntimeException if an error occurs while operator BufferedReader */public static String readFile(String filePath) {    String fileContent = "";    File file = new File(filePath);    if (!file.isFile()) {        return null;    }    BufferedReader reader = null;    try {        InputStreamReader is = new InputStreamReader(new FileInputStream(file));        reader = new BufferedReader(is);        String line;        while ((line = reader.readLine()) != null) {            fileContent += line + " ";        }        reader.close();        return fileContent;    } catch (IOException e) {        e.printStackTrace();    } finally {        if (reader != null) {            try {                reader.close();            } catch (IOException e) {                e.printStackTrace();            }        }    }    return fileContent;}/** * write file * * @param filePath * @param content * @param append   is append, if true, write to the end of file, else clear content of file and write into it * @return return false if content is empty, true otherwise * @throws RuntimeException if an error occurs while operator FileWriter */public static boolean writeFile(String filePath, String content, boolean append) {    if (filePath == null || filePath.length() == 0) {        return false;    }    FileWriter fileWriter = null;    try {        makeDirs(filePath);        fileWriter = new FileWriter(filePath, append);        fileWriter.write(content);        fileWriter.close();        return true;    } catch (IOException e) {        throw new RuntimeException("IOException occurred. ", e);    } finally {        if (fileWriter != null) {            try {                fileWriter.close();            } catch (IOException e) {                throw new RuntimeException("IOException occurred. ", e);            }        }    }}/** * write file * * @param filePath * @param contentList * @param append      is append, if true, write to the end of file, else clear content of file and write into it * @return return false if contentList is empty, true otherwise * @throws RuntimeException if an error occurs while operator FileWriter */public static boolean writeFile(String filePath, List<String> contentList, boolean append) {    if (contentList == null || contentList.size() == 0) {        return false;    }    FileWriter fileWriter = null;    try {        makeDirs(filePath);        fileWriter = new FileWriter(filePath, append);        int i = 0;        for (String line : contentList) {            if (i++ > 0) {                fileWriter.write("\r\n");            }            fileWriter.write(line);        }        fileWriter.close();        return true;    } catch (IOException e) {        throw new RuntimeException("IOException occurred. ", e);    } finally {        if (fileWriter != null) {            try {                fileWriter.close();            } catch (IOException e) {                throw new RuntimeException("IOException occurred. ", e);            }        }    }}/** * write file, the string will be written to the begin of the file * * @param filePath * @param content * @return */public static boolean writeFile(String filePath, String content) {    return writeFile(filePath, content, false);}/** * write file, the string list will be written to the begin of the file * * @param filePath * @param contentList * @return */public static boolean writeFile(String filePath, List<String> contentList) {    return writeFile(filePath, contentList, false);}/** * write file, the bytes will be written to the begin of the file * * @param filePath * @param stream * @return * @see {@link #writeFile(String, InputStream, boolean)} */public static boolean writeFile(String filePath, InputStream stream) {    return writeFile(filePath, stream, false);}/** * write file * * @param stream the input stream * @param append if <code>true</code>, then bytes will be written to the end of the file rather than the beginning * @return return true * @throws RuntimeException if an error occurs while operator FileOutputStream */public static boolean writeFile(String filePath, InputStream stream, boolean append) {    return writeFile(filePath != null ? new File(filePath) : null, stream, append);}/** * write file, the bytes will be written to the begin of the file * * @param file * @param stream * @return * @see {@link #writeFile(File, InputStream, boolean)} */public static boolean writeFile(File file, InputStream stream) {    return writeFile(file, stream, false);}/** * write file * * @param file   the file to be opened for writing. * @param stream the input stream * @param append if <code>true</code>, then bytes will be written to the end of the file rather than the beginning * @return return true * @throws RuntimeException if an error occurs while operator FileOutputStream */public static boolean writeFile(File file, InputStream stream, boolean append) {    OutputStream o = null;    try {        makeDirs(file.getAbsolutePath());        o = new FileOutputStream(file, append);        byte data[] = new byte[1024];        int length = -1;        while ((length = stream.read(data)) != -1) {            o.write(data, 0, length);        }        o.flush();        return true;    } catch (FileNotFoundException e) {        throw new RuntimeException("FileNotFoundException occurred. ", e);    } catch (IOException e) {        throw new RuntimeException("IOException occurred. ", e);    } finally {        if (o != null) {            try {                o.close();                stream.close();            } catch (IOException e) {                throw new RuntimeException("IOException occurred. ", e);            }        }    }}/** * move file * * @param sourceFilePath * @param destFilePath */public static void moveFile(String sourceFilePath, String destFilePath) {    if (TextUtils.isEmpty(sourceFilePath) || TextUtils.isEmpty(destFilePath)) {        throw new RuntimeException("Both sourceFilePath and destFilePath cannot be null.");    }    moveFile(new File(sourceFilePath), new File(destFilePath));}/** * move file * * @param srcFile * @param destFile */public static void moveFile(File srcFile, File destFile) {    boolean rename = srcFile.renameTo(destFile);    if (!rename) {        copyFile(srcFile.getAbsolutePath(), destFile.getAbsolutePath());        deleteFile(srcFile.getAbsolutePath());    }}/** * copy file * * @param sourceFilePath * @param destFilePath * @return * @throws RuntimeException if an error occurs while operator FileOutputStream */public static boolean copyFile(String sourceFilePath, String destFilePath) {    InputStream inputStream = null;    try {        inputStream = new FileInputStream(sourceFilePath);    } catch (FileNotFoundException e) {        throw new RuntimeException("FileNotFoundException occurred. ", e);    }    return writeFile(destFilePath, inputStream);}/** * read file to string list, a element of list is a line * * @param filePath * @param charsetName The name of a supported {@link java.nio.charset.Charset </code>charset<code>} * @return if file not exist, return null, else return content of file * @throws RuntimeException if an error occurs while operator BufferedReader */public static List<String> readFileToList(String filePath, String charsetName) {    File file = new File(filePath);    List<String> fileContent = new ArrayList<String>();    if (file == null || !file.isFile()) {        return null;    }    BufferedReader reader = null;    try {        InputStreamReader is = new InputStreamReader(new FileInputStream(file), charsetName);        reader = new BufferedReader(is);        String line = null;        while ((line = reader.readLine()) != null) {            fileContent.add(line);        }        reader.close();        return fileContent;    } catch (IOException e) {        throw new RuntimeException("IOException occurred. ", e);    } finally {        if (reader != null) {            try {                reader.close();            } catch (IOException e) {                throw new RuntimeException("IOException occurred. ", e);            }        }    }}/** * get file name from path, not include suffix * <p/> * getFileNameWithoutExtension(null)               =   null * getFileNameWithoutExtension("")                 =   "" * getFileNameWithoutExtension("   ")              =   "   " * getFileNameWithoutExtension("abc")              =   "abc" * getFileNameWithoutExtension("a.mp3")            =   "a" * getFileNameWithoutExtension("a.b.rmvb")         =   "a.b" * getFileNameWithoutExtension("c:\\")              =   "" * getFileNameWithoutExtension("c:\\a")             =   "a" * getFileNameWithoutExtension("c:\\a.b")           =   "a" * getFileNameWithoutExtension("c:a.txt\\a")        =   "a" * getFileNameWithoutExtension("/home/admin")      =   "admin" * getFileNameWithoutExtension("/home/admin/a.txt/b.mp3")  =   "b" * * @param filePath * @return file name from path, not include suffix * @see */public static String getFileNameWithoutExtension(String filePath) {    if (filePath == null || filePath.length() == 0) {        return filePath;    }    int extenPosi = filePath.lastIndexOf(FILE_EXTENSION_SEPARATOR);    int filePosi = filePath.lastIndexOf(File.separator);    if (filePosi == -1) {        return (extenPosi == -1 ? filePath : filePath.substring(0, extenPosi));    }    if (extenPosi == -1) {        return filePath.substring(filePosi + 1);    }    return (filePosi < extenPosi ? filePath.substring(filePosi + 1, extenPosi) : filePath.substring(filePosi + 1));}/** * get file name from path, include suffix * <p/> * getFileName(null)               =   null * getFileName("")                 =   "" * getFileName("   ")              =   "   " * getFileName("a.mp3")            =   "a.mp3" * getFileName("a.b.rmvb")         =   "a.b.rmvb" * getFileName("abc")              =   "abc" * getFileName("c:\\")              =   "" * getFileName("c:\\a")             =   "a" * getFileName("c:\\a.b")           =   "a.b" * getFileName("c:a.txt\\a")        =   "a" * getFileName("/home/admin")      =   "admin" * getFileName("/home/admin/a.txt/b.mp3")  =   "b.mp3" * * @param filePath * @return file name from path, include suffix */public static String getFileName(String filePath) {    if (filePath == null || filePath.length() == 0) {        return filePath;    }    int filePosi = filePath.lastIndexOf(File.separator);    return (filePosi == -1) ? filePath : filePath.substring(filePosi + 1);}/** * get folder name from path * <p/> * getFolderName(null)               =   null * getFolderName("")                 =   "" * getFolderName("   ")              =   "" * getFolderName("a.mp3")            =   "" * getFolderName("a.b.rmvb")         =   "" * getFolderName("abc")              =   "" * getFolderName("c:\\")              =   "c:" * getFolderName("c:\\a")             =   "c:" * getFolderName("c:\\a.b")           =   "c:" * getFolderName("c:a.txt\\a")        =   "c:a.txt" * getFolderName("c:a\\b\\c\\d.txt")    =   "c:a\\b\\c" * getFolderName("/home/admin")      =   "/home" * getFolderName("/home/admin/a.txt/b.mp3")  =   "/home/admin/a.txt" * * @param filePath * @return */public static String getFolderName(String filePath) {    if (filePath == null || filePath.length() == 0) {        return filePath;    }    int filePosi = filePath.lastIndexOf(File.separator);    return (filePosi == -1) ? "" : filePath.substring(0, filePosi);}/** * get suffix of file from path * <p/> * getFileExtension(null)               =   "" * getFileExtension("")                 =   "" * getFileExtension("   ")              =   "   " * getFileExtension("a.mp3")            =   "mp3" * getFileExtension("a.b.rmvb")         =   "rmvb" * getFileExtension("abc")              =   "" * getFileExtension("c:\\")              =   "" * getFileExtension("c:\\a")             =   "" * getFileExtension("c:\\a.b")           =   "b" * getFileExtension("c:a.txt\\a")        =   "" * getFileExtension("/home/admin")      =   "" * getFileExtension("/home/admin/a.txt/b")  =   "" * getFileExtension("/home/admin/a.txt/b.mp3")  =   "mp3" * * @param filePath * @return */public static String getFileExtension(String filePath) {    if (filePath == null || filePath.trim().length() == 0) {        return filePath;    }    int extenPosi = filePath.lastIndexOf(FILE_EXTENSION_SEPARATOR);    int filePosi = filePath.lastIndexOf(File.separator);    if (extenPosi == -1) {        return "";    }    return (filePosi >= extenPosi) ? "" : filePath.substring(extenPosi + 1);}/** * Creates the directory named by the trailing filename of this file, including the complete directory path required * to create this directory. * Attentions: * makeDirs("C:\\Users\\Trinea") can only create users folder * makeFolder("C:\\Users\\Trinea\\") can create Trinea folder * * @param filePath * @return true if the necessary directories have been created or the target directory already exists, false one of * the directories can not be created. * if {@link FileUtils#getFolderName(String)} return null, return false * if target directory already exists, return true * return {@link File#makeFolder} */public static boolean makeDirs(String filePath) {    String folderName = getFolderName(filePath);    if (filePath == null || filePath.length() == 0) {        return false;    }    File folder = new File(folderName);    return (folder.exists() && folder.isDirectory()) ? true : folder.mkdirs();}/** * @param filePath * @return * @see #makeDirs(String) */public static boolean makeFolders(String filePath) {    return makeDirs(filePath);}/** * Indicates if this file represents a file on the underlying file system. * * @param filePath * @return */public static boolean isFileExist(String filePath) {    if (filePath == null || filePath.trim().length() == 0) {        return false;    }    File file = new File(filePath);    return (file.exists() && file.isFile());}/** * Indicates if this file represents a directory on the underlying file system. * * @param directoryPath * @return */public static boolean isFolderExist(String directoryPath) {    if (directoryPath == null || directoryPath.trim().length() == 0) {        return false;    }    File dire = new File(directoryPath);    return (dire.exists() && dire.isDirectory());}/** * delete file or directory * * if path is null or empty, return tru * if path not exist, return true * if path exist, delete recursion. return true * * @param path * @return */public static boolean deleteFile(String path) {    if (path == null || path.trim().length() == 0) {        return true;    }    File file = new File(path);    if (!file.exists()) {        return true;    }    if (file.isFile()) {        return file.delete();    }    if (!file.isDirectory()) {        return false;    }    for (File f : file.listFiles()) {        if (f.isFile()) {            f.delete();        } else if (f.isDirectory()) {            deleteFile(f.getAbsolutePath());        }    }    return file.delete();}/** * get file size * if path is null or empty, return -1 * <if path exist and it is a file, return file size, else return -1 * * @param path * @return returns the length of this file in bytes. returns -1 if the file does not exist. */public static long getFileSize(String path) {    if (path == null || path.trim().length() == 0) {        return -1;    }    File file = new File(path);    return (file.exists() && file.isFile() ? file.length() : -1);}

5、字符串转换

/** * 指令字符里很多字符是终结符： \r ，在输出日志的无法打印，为了日志能看到，处理掉这个字符 * * @param bytes 字节 * @return 字符串 */public static String transferForPrint(byte... bytes) {    if (bytes == null)        return null;    return transferForPrint(new String(bytes));}/** * @param str 字符串 * @return 字符串 */public static String transferForPrint(String str) {    if (TextUtils.isEmpty(str))        return str;    str = str.replace('\r', ' ');    str = str.replace('\n', ' ');    if (str.endsWith(">")) {        str = str.substring(0, str.length() - 1);    }    return str;}/** * 转换成 16进制字符串 * * @param b 字节 * @return 字符串 */private static String toHexStr(byte b) {    String str = Integer.toHexString(0xFF & b);    if (str.length() == 1)        str = "0" + str;    return str.toUpperCase();}/** * 转换成 16进制字符串 * * @param bytes 字节 * @return 字符串 */public static String toHexString(byte... bytes) {    if (bytes == null)        return null;    StringBuilder sb = new StringBuilder();    if (bytes.length < 20) {        sb.append("[");        for (int i = 0; i < bytes.length; i++) {            sb.append(toHexStr(bytes[i])).append(",");        }        sb.append("]");    } else {        sb.append("[");        for (int i = 0; i < 4; i++) {            sb.append(toHexStr(bytes[i])).append(",");        }        sb.append("...");        for (int i = bytes.length - 5; i < bytes.length; i++) {            sb.append(toHexStr(bytes[i])).append(",");        }        sb.setLength(sb.length() - 1);        sb.append("]");    }    return sb.toString();}

6、字体操作

//将钥匙使用的字体的类型public static Typeface TEXT_TYPE ;private static Context mContext;// 定义一个私有的构造方法private FrontUtils() {}// 将自身的实例对象设置为一个属性,并加上Static和final修饰符private static final FrontUtils fontUtils = new FrontUtils();// 静态方法返回该类的实例public static FrontUtils getInstance(Context mContext) {    return fontUtils;}public FrontUtils(Context mContext) {    this.mContext = mContext;}/** * 获取应用中将要用到的字体 * 从assets中获取字体资源 * @return */public static Typeface getFont(){    try{        TEXT_TYPE = Typeface.createFromAsset(mContext.getAssets(),"fronts/NotoSansHans-Black.otf");    }catch(Exception e){        TEXT_TYPE = Typeface.DEFAULT;    }    return TEXT_TYPE;}

这些都是在开发中基本会用的到工具类 ，在这里给自己做个笔记，如果和哪位大哥的相同，还望包涵，也在此谢谢您