1，MD5工具类：
public class MD5Util {
public final static String MD5(String s) {
char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
'a', 'b', 'c', 'd', 'e', 'f' };
try {
byte[] btInput = s.getBytes();
// 获得MD5摘要算法的 MessageDigest 对象
MessageDigest mdInst = MessageDigest.getInstance("MD5");
// 使用指定的字节更新摘要
mdInst.update(btInput);
// 获得密文
byte[] md = mdInst.digest();
// 把密文转换成十六进制的字符串形式
int j = md.length;
char str[] = new char[j * 2];
int k = 0;
for (int i = 0; i < j; i++) {
byte byte0 = md[i];
str[k++] = hexDigits[byte0 >>> 4 & 0xf];
str[k++] = hexDigits[byte0 & 0xf];
}
return new String(str);
} catch (Exception e) {
return null;
}
}
public static void main(String[] args) {
System.out.print(MD5Util.MD5("password"));
}
}
2，线程睡眠
public class CSleep {
public static final long DEFAULT_SLEEP_TIME = 500;
private boolean isRuning = false;
public boolean isRuning() {
return isRuning;
}
public void runWithTime(final long defaultSleepTime) {
isRuning = true;
new Thread() {
@Override
public void run() {
try {
sleep(defaultSleepTime, 0);
} catch (InterruptedException e) {
e.printStackTrace();
}
isRuning = false;
super.run();
}
}.start();
}
}
3，检查网络是否连通
/**
* 检查网络是否连通
*
* @return boolean
* @since V1.0
*/
public boolean isNetworkAvailable(Context context) {
// 创建并初始化连接对象
ConnectivityManager connMan = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
// 判断初始化是否成功并作出相应处理
if (connMan != null) {
// 调用getActiveNetworkInfo方法创建对象,如果不为空则表明网络连通，否则没连通
NetworkInfo info = connMan.getActiveNetworkInfo();
if (info != null) {
return info.isAvailable();
}
}
return false;
}
4，异常类捕捉
/**
* UncaughtException处理类,当程序发生Uncaught异常的时候,由该类来接管程序,并记录发送错误报告. 需要在Application中注册，为了要在程序启动器就监控整个程序。
*/
public class CrashHandler implements UncaughtExceptionHandler {
/** TAG */
public static final String TAG = "CrashHandler";
/** 系统默认的UncaughtException处理类 */
private Thread.UncaughtExceptionHandler mDefaultHandler;
/** CrashHandler实例 */
private static CrashHandler mCrashHandler;
/** 程序的Context对象 */
private Context mContext;
/** 用来存储设备信息和异常信息 */
private Map<String, String> infos = new HashMap<String, String>();
/** 用于格式化日期,作为日志文件名的一部分 */
private DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss"); /**
* 私有构造函数
*/
private CrashHandler() { } /**
* 获取CrashHandler实例 ,单例模式
*
* @return
* @since V1.0
*/
public static CrashHandler getInstance() {
if (mCrashHandler == null)
mCrashHandler = new CrashHandler();
return mCrashHandler;
} /**
* 初始化
*
* @param context
* @since V1.0
*/
public void init(Context context) {
mContext = context;
// 获取系统默认的UncaughtException处理器
mDefaultHandler = Thread.getDefaultUncaughtExceptionHandler();
// 设置该CrashHandler为程序的默认处理器
Thread.setDefaultUncaughtExceptionHandler(this);
} /**
* 当UncaughtException发生时会转入该函数来处理
*/
@Override
public void uncaughtException(Thread thread, Throwable ex) {
if (!handleException(ex) && mDefaultHandler != null) {
// 如果用户没有处理则让系统默认的异常处理器来处理
mDefaultHandler.uncaughtException(thread, ex);
} else {
try {
Thread.sleep(3000);
} catch (InterruptedException e) {
CLog.e(TAG, "uncaughtException() InterruptedException:" + e);
}
// 退出程序
android.os.Process.killProcess(android.os.Process.myPid());
System.exit(1);
}
} /**
* 自定义错误处理,收集错误信息 发送错误报告等操作均在此完成.
*
* @param ex
* @return true:如果处理了该异常信息;否则返回false.
* @since V1.0
*/
private boolean handleException(Throwable ex) {
if (ex == null) {
return false;
} // 收集设备参数信息
collectDeviceInfo(mContext); // 使用Toast来显示异常信息
new Thread() {
@Override
public void run() {
Looper.prepare();
Toast.makeText(mContext, "很抱歉,程序出现异常,即将退出.", Toast.LENGTH_SHORT).show();
Looper.loop();
}
}.start(); // 保存日志文件
saveCatchInfo2File(ex);
return true;
} /**
* 收集设备参数信息
*
* @param ctx
* @since V1.0
*/
public void collectDeviceInfo(Context ctx) {
try {
PackageManager pm = ctx.getPackageManager();
PackageInfo pi = pm.getPackageInfo(ctx.getPackageName(), PackageManager.GET_ACTIVITIES);
if (pi != null) {
String versionName = pi.versionName == null ? "null" : pi.versionName;
String versionCode = pi.versionCode + "";
infos.put("versionName", versionName);
infos.put("versionCode", versionCode);
}
} catch (NameNotFoundException e) {
CLog.e(TAG, "collectDeviceInfo() an error occured when collect package info NameNotFoundException:", e);
}
Field[] fields = Build.class.getDeclaredFields();
for (Field field : fields) {
try {
field.setAccessible(true);
infos.put(field.getName(), field.get(null).toString());
CLog.d(TAG, field.getName() + " : " + field.get(null));
} catch (Exception e) {
CLog.e(TAG, "collectDeviceInfo() an error occured when collect crash info Exception:", e);
}
}
} /**
* 保存错误信息到文件中
*
* @param ex
* @return 返回文件名称,便于将文件传送到服务器
*/
private String saveCatchInfo2File(Throwable ex) {
StringBuffer sb = new StringBuffer();
for (Map.Entry<String, String> entry : infos.entrySet()) {
String key = entry.getKey();
String value = entry.getValue();
sb.append(key + "=" + value + "\n");
} Writer writer = new StringWriter();
PrintWriter printWriter = new PrintWriter(writer);
ex.printStackTrace(printWriter);
Throwable cause = ex.getCause();
while (cause != null) {
cause.printStackTrace(printWriter);
cause = cause.getCause();
}
printWriter.close();
String result = writer.toString();
sb.append(result);
try {
long timestamp = System.currentTimeMillis();
String time = formatter.format(new Date());
String fileName = "crash-" + time + "-" + timestamp + ".log";
if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
String path = FilePathUtil.getiVMSDirPath() + "/crash/";
File dir = new File(path);
if (!dir.exists()) {
dir.mkdirs();
}
FileOutputStream fos = new FileOutputStream(path + fileName);
fos.write(sb.toString().getBytes());
// 发送给开发人员
sendCrashLog2PM(path + fileName);
fos.close();
}
return fileName;
} catch (Exception e) {
CLog.e(TAG, "saveCatchInfo2File() an error occured while writing file... Exception:", e);
}
return null;
} /**
* 将捕获的导致崩溃的错误信息发送给开发人员 目前只将log日志保存在sdcard 和输出到LogCat中，并未发送给后台。
*
* @param fileName
* @since V1.0
*/
private void sendCrashLog2PM(String fileName) {
if (!new File(fileName).exists()) {
CLog.e(TAG, "sendCrashLog2PM() 日志文件不存在");
return;
}
FileInputStream fis = null;
BufferedReader reader = null;
String s = null;
try {
fis = new FileInputStream(fileName);
reader = new BufferedReader(new InputStreamReader(fis, "GBK"));
while (true) {
s = reader.readLine();
if (s == null)
break;
// 由于目前尚未确定以何种方式发送，所以先打出log日志。
CLog.e(TAG, s);
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally { // 关闭流
try {
reader.close();
fis.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
5，弹出框提醒
public static Dialog showDialog(Context ctx, int layViewID, int ThemeType) {
Dialog res = new Dialog(ctx, ThemeType);
res.setContentView(layViewID);
return res;
}
6，图片API类
public class ImageAPI {
public static Bitmap getImageByFilePath(String filePath, int scale) {
Bitmap res = null;
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(filePath, options);
options.inJustDecodeBounds = false;
options.inSampleSize = scale;
options.inPreferredConfig = Bitmap.Config.ARGB_4444;
return res;
}
public static Bitmap getImageByFilePath(String filePath, int Towidth, int ToHeight) {
Bitmap res = null;
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
if (!new File(filePath).exists())
return res;
BitmapFactory.decodeFile(filePath, options);
int origionalWidth = options.outHeight;
int origionalHeight = options.outWidth;
options.inJustDecodeBounds = false;
int scale = Math.max(origionalWidth / Towidth, origionalHeight / ToHeight);
options.inSampleSize = scale;
options.inPreferredConfig = Bitmap.Config.ARGB_4444;
try {
res = BitmapFactory.decodeFile(filePath, options);
} catch (Exception e) {
e.printStackTrace();
return null;
} catch (OutOfMemoryError e) {
e.printStackTrace();
return null;
}
return res;
}
}
10，提醒封装类
public static void showToast(Context ctx, int id, String str) {
if (str == null) {
return;
}
Toast toast = Toast.makeText(ctx, ctx.getString(id) + str, Toast.LENGTH_SHORT);
toast.setGravity(Gravity.CENTER, 0, 0);
toast.show();
}
public static void showToast(Context ctx, String errInfo) {
if (errInfo == null) {
return;
}
Toast toast = Toast.makeText(ctx, errInfo, Toast.LENGTH_SHORT);
toast.setGravity(Gravity.CENTER, 0, 0);
toast.show();
}
阅读扩展
源于对掌握的Android开发基础点进行整理，罗列下已经总结的文章，从中可以看到技术积累的过程。
17，View 的事件体系
18，View 的工作原理
22，Android 性能优化
23，Android 消息机制