作者：LiJinlun 字体：[增加 减小] 类型：转载 时间：2016-01-24 我要评论
这篇文章主要介绍了实例详解Android快速开发工具类总结的相关资料,需要的朋友可以参考下一、日志工具类 Log.java
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public class L
{
private L()
{
/* 不可被实例化 */
throw new UnsupportedOperationException("Cannot be instantiated!");
}
// 是否需要打印bug，可以在application的onCreate函数里面初始化
public static boolean isDebug = true;
private static final String TAG = "DefaultTag";
// 下面四个是默认tag的函数
public static void i(String msg)
{
if (isDebug)
Log.i(TAG, msg);
}
public static void d(String msg)
{
if (isDebug)
Log.d(TAG, msg);
}
public static void e(String msg)
{
if (isDebug)
Log.e(TAG, msg);
}
public static void v(String msg)
{
if (isDebug)
Log.v(TAG, msg);
}
// 下面是传入自定义tag的函数
public static void i(String tag, String msg)
{
if (isDebug)
Log.i(tag, msg);
}
public static void d(String tag, String msg)
{
if (isDebug)
Log.i(tag, msg);
}
public static void e(String tag, String msg)
{
if (isDebug)
Log.i(tag, msg);
}
public static void v(String tag, String msg)
{
if (isDebug)
Log.i(tag, msg);
}
}
二、Toast统一管理类 Tost.java
? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58public class T
{
private T()
{
/* cannot be instantiated */
throw new UnsupportedOperationException("cannot be instantiated");
}
public static boolean isShow = true;
/**
* 短时间显示Toast
*/
public static void showShort(Context context, CharSequence message)
{
if (isShow)
Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
}
/**
* 短时间显示Toast
* @param message 要显示的字符串资源的id
*/
public static void showShort(Context context, int message)
{
if (isShow)
Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
}
/**
* 长时间显示Toast
*/
public static void showLong(Context context, CharSequence message)
{
if (isShow)
Toast.makeText(context, message, Toast.LENGTH_LONG).show();
}
/**
* 长时间显示Toast
*/
public static void showLong(Context context, int message)
{
if (isShow)
Toast.makeText(context, message, Toast.LENGTH_LONG).show();
}
/**
* 自定义显示Toast时间
*/
public static void show(Context context, CharSequence message, int duration)
{
if (isShow)
Toast.makeText(context, message, duration).show();
}
/**
* 自定义显示Toast时间
*/
public static void show(Context context, int message, int duration)
{
if (isShow)
Toast.makeText(context, message, duration).show();
}
}
三、SharedPreferences封装类 SPUtils.java 和 PreferencesUtils.java
1. SPUtils.java
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{
/**
* 保存在手机里面的文件名
*/
public static final String FILE_NAME = "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;
}
/**
* 移除某个key值已经对应的值
* @param context
* @param key
*/
public static void remove(Context context, String key)
{
SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sp.edit();
editor.remove(key);
SharedPreferencesCompat.apply(editor);
}
/**
* 清除所有数据
* @param context
*/
public static void clear(Context context)
{
SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sp.edit();
editor.clear();
SharedPreferencesCompat.apply(editor);
}
/**
* 查询某个key是否已经存在
* @param context
* @param key
* @return
*/
public static boolean contains(Context context, String key)
{
SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
Context.MODE_PRIVATE);
return sp.contains(key);
}
/**
* 返回所有的键值对
*
* @param context
* @return
*/
public static Map<String, ?> getAll(Context context)
{
SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
Context.MODE_PRIVATE);
return sp.getAll();
}
/**
* 创建一个解决SharedPreferencesCompat.apply方法的一个兼容类
*
* @author zhy
*
*/
private static class SharedPreferencesCompat
{
private static final Method sApplyMethod = findApplyMethod();
/**
* 反射查找apply的方法
*
* @return
*/
@SuppressWarnings({ "unchecked", "rawtypes" })
private static Method findApplyMethod()
{
try
{
Class clz = SharedPreferences.Editor.class;
return clz.getMethod("apply");
} catch (NoSuchMethodException e)
{
}
return null;
}
/**
* 如果找到则使用apply执行，否则使用commit
*
* @param editor
*/
public static void apply(SharedPreferences.Editor editor)
{
try
{
if (sApplyMethod != null)
{
sApplyMethod.invoke(editor);
return;
}
} catch (IllegalArgumentException e)
{
} catch (IllegalAccessException e)
{
} catch (InvocationTargetException e)
{
}
editor.commit();
}
}
}
对SharedPreference的使用做了建议的封装，对外公布出put，get，remove，clear等等方法；
注意一点，里面所有的commit操作使用了SharedPreferencesCompat.apply进行了替代，目的是尽可能的使用apply代替commit.
首先说下为什么，因为commit方法是同步的，并且我们很多时候的commit操作都是UI线程中，毕竟是IO操作，尽可能异步；
所以我们使用apply进行替代，apply异步的进行写入；
但是apply相当于commit来说是new API呢，为了更好的兼容，我们做了适配；
SharedPreferencesCompat也可以给大家创建兼容类提供了一定的参考
2. SPUtils.java
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public static String PREFERENCE_NAME = "TrineaAndroidCommon";
private PreferencesUtils() {
throw new AssertionError();
}
/**
* put string preferences
*
* @param context
* @param key The name of the preference to modify
* @param value The new value for the preference
* @return True if the new values were successfully written to persistent storage.
*/
public static boolean putString(Context context, String key, String value) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = settings.edit();
editor.putString(key, value);
return editor.commit();
}
/**
* get string preferences
*
* @param context
* @param key The name of the preference to retrieve
* @return The preference value if it exists, or null. Throws ClassCastException if there is a preference with this
* name that is not a string
* @see #getString(Context, String, String)
*/
public static String getString(Context context, String key) {
return getString(context, key, null);
}
/**
* get string preferences
*
* @param context
* @param key The name of the preference to retrieve
* @param defaultValue Value to return if this preference does not exist
* @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with
* this name that is not a string
*/
public static String getString(Context context, String key, String defaultValue) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
return settings.getString(key, defaultValue);
}
/**
* put int preferences
*
* @param context
* @param key The name of the preference to modify
* @param value The new value for the preference
* @return True if the new values were successfully written to persistent storage.
*/
public static boolean putInt(Context context, String key, int value) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = settings.edit();
editor.putInt(key, value);
return editor.commit();
}
/**
* get int preferences
*
* @param context
* @param key The name of the preference to retrieve
* @return The preference value if it exists, or -. Throws ClassCastException if there is a preference with this
* name that is not a int
* @see #getInt(Context, String, int)
*/
public static int getInt(Context context, String key) {
return getInt(context, key, -);
}
/**
* get int preferences
*
* @param context
* @param key The name of the preference to retrieve
* @param defaultValue Value to return if this preference does not exist
* @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with
* this name that is not a int
*/
public static int getInt(Context context, String key, int defaultValue) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
return settings.getInt(key, defaultValue);
}
/**
* put long preferences
*
* @param context
* @param key The name of the preference to modify
* @param value The new value for the preference
* @return True if the new values were successfully written to persistent storage.
*/
public static boolean putLong(Context context, String key, long value) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = settings.edit();
editor.putLong(key, value);
return editor.commit();
}
/**
* get long preferences
*
* @param context
* @param key The name of the preference to retrieve
* @return The preference value if it exists, or -. Throws ClassCastException if there is a preference with this
* name that is not a long
* @see #getLong(Context, String, long)
*/
public static long getLong(Context context, String key) {
return getLong(context, key, -);
}
/**
* get long preferences
*
* @param context
* @param key The name of the preference to retrieve
* @param defaultValue Value to return if this preference does not exist
* @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with
* this name that is not a long
*/
public static long getLong(Context context, String key, long defaultValue) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
return settings.getLong(key, defaultValue);
}
/**
* put float preferences
*
* @param context
* @param key The name of the preference to modify
* @param value The new value for the preference
* @return True if the new values were successfully written to persistent storage.
*/
public static boolean putFloat(Context context, String key, float value) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = settings.edit();
editor.putFloat(key, value);
return editor.commit();
}
/**
* get float preferences
*
* @param context
* @param key The name of the preference to retrieve
* @return The preference value if it exists, or -. Throws ClassCastException if there is a preference with this
* name that is not a float
* @see #getFloat(Context, String, float)
*/
public static float getFloat(Context context, String key) {
return getFloat(context, key, -);
}
/**
* get float preferences
*
* @param context
* @param key The name of the preference to retrieve
* @param defaultValue Value to return if this preference does not exist
* @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with
* this name that is not a float
*/
public static float getFloat(Context context, String key, float defaultValue) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
return settings.getFloat(key, defaultValue);
}
/**
* put boolean preferences
*
* @param context
* @param key The name of the preference to modify
* @param value The new value for the preference
* @return True if the new values were successfully written to persistent storage.
*/
public static boolean putBoolean(Context context, String key, boolean value) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = settings.edit();
editor.putBoolean(key, value);
return editor.commit();
}
/**
* get boolean preferences, default is false
*
* @param context
* @param key The name of the preference to retrieve
* @return The preference value if it exists, or false. Throws ClassCastException if there is a preference with this
* name that is not a boolean
* @see #getBoolean(Context, String, boolean)
*/
public static boolean getBoolean(Context context, String key) {
return getBoolean(context, key, false);
}
/**
* get boolean preferences
*
* @param context
* @param key The name of the preference to retrieve
* @param defaultValue Value to return if this preference does not exist
* @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with
* this name that is not a boolean
*/
public static boolean getBoolean(Context context, String key, boolean defaultValue) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
return settings.getBoolean(key, defaultValue);
}
}
四、单位转换类 DensityUtils.java
? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55public class DensityUtils
{
private DensityUtils()
{
/* cannot be instantiated */
throw new UnsupportedOperationException("cannot be instantiated");
}
/**
* dp转px
*
* @param context
* @param val
* @return
*/
public static int dppx(Context context, float dpVal)
{
return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
dpVal, context.getResources().getDisplayMetrics());
}
/**
* sp转px
*
* @param context
* @param val
* @return
*/
public static int sppx(Context context, float spVal)
{
return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP,
spVal, context.getResources().getDisplayMetrics());
}
/**
* px转dp
*
* @param context
* @param pxVal
* @return
*/
public static float pxdp(Context context, float pxVal)
{
final float scale = context.getResources().getDisplayMetrics().density;
return (pxVal / scale);
}
/**
* px转sp
*
* @param fontScale
* @param pxVal
* @return
*/
public static float pxsp(Context context, float pxVal)
{
return (pxVal / context.getResources().getDisplayMetrics().scaledDensity);
}
}
TypedValue：
Container for a dynamically typed data value. Primarily used with Resources for holding resource values.
applyDimension(int unit, float value, DisplayMetrics metrics)：
Converts an unpacked complex data value holding a dimension to its final floating point value.
五、SD卡相关辅助类 SDCardUtils.java
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{
private SDCardUtils()
{
/* cannot be instantiated */
throw new UnsupportedOperationException("cannot be instantiated");
}
/**
* 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() - ;
// 获取单个数据块的大小（byte）
long freeBlocks = stat.getAvailableBlocks();
return freeBlocks * availableBlocks;
}
return ;
}
/**
* 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() - ;
return stat.getBlockSize() * availableBlocks;
}
/**
* 获取系统存储路径
*
* @return
*/
public static String getRootDirectoryPath()
{
return Environment.getRootDirectory().getAbsolutePath();
}
}
StatFs 是Android提供的一个类：
Retrieve overall information about the space on a filesystem. This is a wrapper for Unix statvfs().
检索一个文件系统的整体信息空间。这是一个Unix statvfs() 包装器
六、屏幕相关辅助类 ScreenUtils.java
? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100public class ScreenUtils
{
private ScreenUtils()
{
/* cannot be instantiated */
throw new UnsupportedOperationException("cannot be instantiated");
}
/**
* 获得屏幕高度
*
* @param context
* @return
*/
public static int getScreenWidth(Context context)
{
WindowManager wm = (WindowManager) context
.getSystemService(Context.WINDOW_SERVICE);
DisplayMetrics outMetrics = new DisplayMetrics();
wm.getDefaultDisplay().getMetrics(outMetrics);
return outMetrics.widthPixels;
}
/**
* 获得屏幕宽度
*
* @param context
* @return
*/
public static int getScreenHeight(Context context)
{
WindowManager wm = (WindowManager) context
.getSystemService(Context.WINDOW_SERVICE);
DisplayMetrics outMetrics = new DisplayMetrics();
wm.getDefaultDisplay().getMetrics(outMetrics);
return outMetrics.heightPixels;
}
/**
* 获得状态栏的高度
*
* @param context
* @return
*/
public static int getStatusHeight(Context context)
{
int statusHeight = -;
try
{
Class<?> clazz = Class.forName("com.android.internal.R$dimen");
Object object = clazz.newInstance();
int height = Integer.parseInt(clazz.getField("status_bar_height")
.get(object).toString());
statusHeight = context.getResources().getDimensionPixelSize(height);
} catch (Exception e)
{
e.printStackTrace();
}
return statusHeight;
}
/**
* 获取当前屏幕截图，包含状态栏
*
* @param activity
* @return
*/
public static Bitmap snapShotWithStatusBar(Activity activity)
{
View view = activity.getWindow().getDecorView();
view.setDrawingCacheEnabled(true);
view.buildDrawingCache();
Bitmap bmp = view.getDrawingCache();
int width = getScreenWidth(activity);
int height = getScreenHeight(activity);
Bitmap bp = null;
bp = Bitmap.createBitmap(bmp, , , width, height);
view.destroyDrawingCache();
return bp;
}
/**
* 获取当前屏幕截图，不包含状态栏
*
* @param activity
* @return
*/
public static Bitmap snapShotWithoutStatusBar(Activity activity)
{
View view = activity.getWindow().getDecorView();
view.setDrawingCacheEnabled(true);
view.buildDrawingCache();
Bitmap bmp = view.getDrawingCache();
Rect frame = new Rect();
activity.getWindow().getDecorView().getWindowVisibleDisplayFrame(frame);
int statusBarHeight = frame.top;
int width = getScreenWidth(activity);
int height = getScreenHeight(activity);
Bitmap bp = null;
bp = Bitmap.createBitmap(bmp, , statusBarHeight, width, height
- statusBarHeight);
view.destroyDrawingCache();
return bp;
}
}
七、App相关辅助类 APPUtils.java
? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46public class AppUtils
{
private AppUtils()
{
/* cannot be instantiated */
throw new UnsupportedOperationException("cannot be instantiated");
}
/**
* 获取应用程序名称
*/
public static String getAppName(Context context)
{
try
{
PackageManager packageManager = context.getPackageManager();
PackageInfo packageInfo = packageManager.getPackageInfo(
context.getPackageName(), );
int labelRes = packageInfo.applicationInfo.labelRes;
return context.getResources().getString(labelRes);
} catch (NameNotFoundException e)
{
e.printStackTrace();
}
return null;
}
/**
* [获取应用程序版本名称信息]
*
* @param context
* @return 当前应用的版本名称
*/
public static String getVersionName(Context context)
{
try
{
PackageManager packageManager = context.getPackageManager();
PackageInfo packageInfo = packageManager.getPackageInfo(
context.getPackageName(), );
return packageInfo.versionName;
} catch (NameNotFoundException e)
{
e.printStackTrace();
}
return null;
}
}
八、软键盘相关辅助类KeyBoardUtils.java
? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32/**
* 打开或关闭软键盘
*/
public class KeyBoardUtils
{
/**
* 打卡软键盘
*
* @param mEditText 输入框
* @param mContext 上下文
*/
public static void openKeybord(EditText mEditText, Context mContext)
{
InputMethodManager imm = (InputMethodManager) mContext
.getSystemService(Context.INPUT_METHOD_SERVICE);
imm.showSoftInput(mEditText, InputMethodManager.RESULT_SHOWN);
imm.toggleSoftInput(InputMethodManager.SHOW_FORCED,
InputMethodManager.HIDE_IMPLICIT_ONLY);
}
/**
* 关闭软键盘
*
* @param mEditText 输入框
* @param mContext 上下文
*/
public static void closeKeybord(EditText mEditText, Context mContext)
{
InputMethodManager imm = (InputMethodManager) mContext
.getSystemService(Context.INPUT_METHOD_SERVICE);
imm.hideSoftInputFromWindow(mEditText.getWindowToken(), );
}
}
九、网络相关辅助类 NetUtils.java
? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51public class NetUtils
{
private NetUtils()
{
/* cannot be instantiated */
throw new UnsupportedOperationException("cannot be instantiated");
}
/**
* 判断网络是否连接
*/
public static boolean isConnected(Context context)
{
ConnectivityManager connectivity = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
if (null != connectivity)
{
NetworkInfo info = connectivity.getActiveNetworkInfo();
if (null != info && info.isConnected())
{
if (info.getState() == NetworkInfo.State.CONNECTED)
{
return true;
}
}
}
return false;
}
/**
* 判断是否是wifi连接
*/
public static boolean isWifi(Context context)
{
ConnectivityManager cm = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
if (cm == null)
return false;
return cm.getActiveNetworkInfo().getType() == ConnectivityManager.TYPE_WIFI;
}
/**
* 打开网络设置界面
*/
public static void openSetting(Activity activity)
{
Intent intent = new Intent("/");
ComponentName cm = new ComponentName("com.android.settings",
"com.android.settings.WirelessSettings");
intent.setComponent(cm);
intent.setAction("android.intent.action.VIEW");
activity.startActivityForResult(intent, );
}
}
十、Http相关辅助类 HttpUtils.java
? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201/**
* Http请求的工具类
*/
public class HttpUtils
{
private static final int TIMEOUT_IN_MILLIONS = ;
public interface CallBack
{
void onRequestComplete(String result);
}
/**
* 异步的Get请求
*
* @param urlStr
* @param callBack
*/
public static void doGetAsyn(final String urlStr, final CallBack callBack)
{
new Thread()
{
public void run()
{
try
{
String result = doGet(urlStr);
if (callBack != null)
{
callBack.onRequestComplete(result);
}
} catch (Exception e)
{
e.printStackTrace();
}
};
}.start();
}
/**
* 异步的Post请求
* @param urlStr
* @param params
* @param callBack
* @throws Exception
*/
public static void doPostAsyn(final String urlStr, final String params,
final CallBack callBack) throws Exception
{
new Thread()
{
public void run()
{
try
{
String result = doPost(urlStr, params);
if (callBack != null)
{
callBack.onRequestComplete(result);
}
} catch (Exception e)
{
e.printStackTrace();
}
};
}.start();
}
/**
* Get请求，获得返回数据
*
* @param urlStr
* @return
* @throws Exception
*/
public static String doGet(String urlStr)
{
URL url = null;
HttpURLConnection conn = null;
InputStream is = null;
ByteArrayOutputStream baos = null;
try
{
url = new URL(urlStr);
conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(TIMEOUT_IN_MILLIONS);
conn.setConnectTimeout(TIMEOUT_IN_MILLIONS);
conn.setRequestMethod("GET");
conn.setRequestProperty("accept", "*/*");
conn.setRequestProperty("connection", "Keep-Alive");
if (conn.getResponseCode() == )
{
is = conn.getInputStream();
baos = new ByteArrayOutputStream();
int len = -;
byte[] buf = new byte[];
while ((len = is.read(buf)) != -)
{
baos.write(buf, , len);
}
baos.flush();
return baos.toString();
} else
{
throw new RuntimeException(" responseCode is not ... ");
}
} catch (Exception e)
{
e.printStackTrace();
} finally
{
try
{
if (is != null)
is.close();
} catch (IOException e)
{
}
try
{
if (baos != null)
baos.close();
} catch (IOException e)
{
}
conn.disconnect();
}
return null ;
}
/**
* 向指定 URL 发送POST方法的请求
*
* @param url
* 发送请求的 URL
* @param param
* 请求参数，请求参数应该是 name=value&name=value 的形式。
* @return 所代表远程资源的响应结果
* @throws Exception
*/
public static String doPost(String url, String param)
{
PrintWriter out = null;
BufferedReader in = null;
String result = "";
try
{
URL realUrl = new URL(url);
// 打开和URL之间的连接
HttpURLConnection conn = (HttpURLConnection) realUrl
.openConnection();
// 设置通用的请求属性
conn.setRequestProperty("accept", "*/*");
conn.setRequestProperty("connection", "Keep-Alive");
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type",
"application/x-www-form-urlencoded");
conn.setRequestProperty("charset", "utf-");
conn.setUseCaches(false);
// 发送POST请求必须设置如下两行
conn.setDoOutput(true);
conn.setDoInput(true);
conn.setReadTimeout(TIMEOUT_IN_MILLIONS);
conn.setConnectTimeout(TIMEOUT_IN_MILLIONS);
if (param != null && !param.trim().equals(""))
{
// 获取URLConnection对象对应的输出流
out = new PrintWriter(conn.getOutputStream());
// 发送请求参数
out.print(param);
// flush输出流的缓冲
out.flush();
}
// 定义BufferedReader输入流来读取URL的响应
in = new BufferedReader(
new InputStreamReader(conn.getInputStream()));
String line;
while ((line = in.readLine()) != null)
{
result += line;
}
} catch (Exception e)
{
e.printStackTrace();
}
// 使用finally块来关闭输出流、输入流
finally
{
try
{
if (out != null)
{
out.close();
}
if (in != null)
{
in.close();
}
} catch (IOException ex)
{
ex.printStackTrace();
}
}
return result;
}
}
十一、时间工具类 TimeUtils.java
? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52public class TimeUtils {
public static final SimpleDateFormat DEFAULT_DATE_FORMAT =
new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
public static final SimpleDateFormat DATE_FORMAT_DATE =
new SimpleDateFormat("yyyy-MM-dd");
private TimeUtils() {
throw new AssertionError();
}
/**
* long time to string
*
* @param timeInMillis
* @param dateFormat
* @return
*/
public static String getTime(long timeInMillis, SimpleDateFormat dateFormat) {
return dateFormat.format(new Date(timeInMillis));
}
/**
* long time to string, format is {@link #DEFAULT_DATE_FORMAT}
*
* @param timeInMillis
* @return
*/
public static String getTime(long timeInMillis) {
return getTime(timeInMillis, DEFAULT_DATE_FORMAT);
}
/**
* get current time in milliseconds
*
* @return
*/
public static long getCurrentTimeInLong() {
return System.currentTimeMillis();
}
/**
* get current time in milliseconds, format is {@link #DEFAULT_DATE_FORMAT}
*
* @return
*/
public static String getCurrentTimeInString() {
return getTime(getCurrentTimeInLong());
}
/**
* get current time in milliseconds
*
* @return
*/
public static String getCurrentTimeInString(SimpleDateFormat dateFormat) {
return getTime(getCurrentTimeInLong(), dateFormat);
}
}
十二、文件工具类 FileUtils.java
? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487
public class FileUtils {
public final static String FILE_EXTENSION_SEPARATOR = ".";
private FileUtils() {
throw new AssertionError();
}
/**
* read file
*
* @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 StringBuilder readFile(String filePath, String charsetName) {
File file = new File(filePath);
StringBuilder fileContent = new StringBuilder("");
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) {
if (!fileContent.toString().equals("")) {
fileContent.append("\r\n");
}
fileContent.append(line);
}
return fileContent;
} catch (IOException e) {
throw new RuntimeException("IOException occurred. ", e);
} finally {
IOUtils.close(reader);
}
}
/**
* 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 (StringUtils.isEmpty(content)) {
return false;
}
FileWriter fileWriter = null;
try {
makeDirs(filePath);
fileWriter = new FileWriter(filePath, append);
fileWriter.write(content);
return true;
} catch (IOException e) {
throw new RuntimeException("IOException occurred. ", e);
} finally {
IOUtils.close(fileWriter);
}
}
/**
* 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 (ListUtils.isEmpty(contentList)) {
return false;
}
FileWriter fileWriter = null;
try {
makeDirs(filePath);
fileWriter = new FileWriter(filePath, append);
int i = ;
for (String line : contentList) {
if (i++ > ) {
fileWriter.write("\r\n");
}
fileWriter.write(line);
}
return true;
} catch (IOException e) {
throw new RuntimeException("IOException occurred. ", e);
} finally {
IOUtils.close(fileWriter);
}
}
/**
* 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 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(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[];
int length = -;
while ((length = stream.read(data)) != -) {
o.write(data, , length);
}
o.flush();
return true;
} catch (FileNotFoundException e) {
throw new RuntimeException("FileNotFoundException occurred. ", e);
} catch (IOException e) {
throw new RuntimeException("IOException occurred. ", e);
} finally {
IOUtils.close(o);
IOUtils.close(stream);
}
}
/**
* 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);
}
return fileContent;
} catch (IOException e) {
throw new RuntimeException("IOException occurred. ", e);
} finally {
IOUtils.close(reader);
}
}
/**
* get file name from path, not include suffix
*
* <pre>
* getFileNameWithoutExtension(null) = null
* getFileNameWithoutExtension("") = ""
* getFileNameWithoutExtension(" ") = " "
* getFileNameWithoutExtension("abc") = "abc"
* getFileNameWithoutExtension("a.mp") = "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.mp") = "b"
* </pre>
*
* @param filePath
* @return file name from path, not include suffix
* @see
*/
public static String getFileNameWithoutExtension(String filePath) {
if (StringUtils.isEmpty(filePath)) {
return filePath;
}
int extenPosi = filePath.lastIndexOf(FILE_EXTENSION_SEPARATOR);
int filePosi = filePath.lastIndexOf(File.separator);
if (filePosi == -) {
return (extenPosi == - ? filePath : filePath.substring(, extenPosi));
}
if (extenPosi == -) {
return filePath.substring(filePosi + );
}
return (filePosi < extenPosi ? filePath.substring(filePosi + , extenPosi) : filePath.substring(filePosi + ));
}
/**
* get file name from path, include suffix
*
* <pre>
* getFileName(null) = null
* getFileName("") = ""
* getFileName(" ") = " "
* getFileName("a.mp") = "a.mp"
* 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.mp") = "b.mp"
* </pre>
*
* @param filePath
* @return file name from path, include suffix
*/
public static String getFileName(String filePath) {
if (StringUtils.isEmpty(filePath)) {
return filePath;
}
int filePosi = filePath.lastIndexOf(File.separator);
return (filePosi == -) ? filePath : filePath.substring(filePosi + );
}
/**
* get folder name from path
*
* <pre>
* getFolderName(null) = null
* getFolderName("") = ""
* getFolderName(" ") = ""
* getFolderName("a.mp") = ""
* 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.mp") = "/home/admin/a.txt"
* </pre>
*
* @param filePath
* @return
*/
public static String getFolderName(String filePath) {
if (StringUtils.isEmpty(filePath)) {
return filePath;
}
int filePosi = filePath.lastIndexOf(File.separator);
return (filePosi == -) ? "" : filePath.substring(, filePosi);
}
/**
* get suffix of file from path
*
* <pre>
* getFileExtension(null) = ""
* getFileExtension("") = ""
* getFileExtension(" ") = " "
* getFileExtension("a.mp") = "mp"
* 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.mp") = "mp"
* </pre>
*
* @param filePath
* @return
*/
public static String getFileExtension(String filePath) {
if (StringUtils.isBlank(filePath)) {
return filePath;
}
int extenPosi = filePath.lastIndexOf(FILE_EXTENSION_SEPARATOR);
int filePosi = filePath.lastIndexOf(File.separator);
if (extenPosi == -) {
return "";
}
return (filePosi >= extenPosi) ? "" : filePath.substring(extenPosi + );
}
/**
* Creates the directory named by the trailing filename of this file, including the complete directory path required
* to create this directory. <br/>
* <br/>
* <ul>
* <strong>Attentions:</strong>
* <li>makeDirs("C:\\Users\\Trinea") can only create users folder</li>
* <li>makeFolder("C:\\Users\\Trinea\\") can create Trinea folder</li>
* </ul>
*
* @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.
* <ul>
* <li>if {@link FileUtils#getFolderName(String)} return null, return false</li>
* <li>if target directory already exists, return true</li>
* <li>return {@link java.io.File#makeFolder}</li>
* </ul>
*/
public static boolean makeDirs(String filePath) {
String folderName = getFolderName(filePath);
if (StringUtils.isEmpty(folderName)) {
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 (StringUtils.isBlank(filePath)) {
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 (StringUtils.isBlank(directoryPath)) {
return false;
}
File dire = new File(directoryPath);
return (dire.exists() && dire.isDirectory());
}
/**
* delete file or directory
* <ul>
* <li>if path is null or empty, return true</li>
* <li>if path not exist, return true</li>
* <li>if path exist, delete recursion. return true</li>
* <ul>
*
* @param path
* @return
*/
public static boolean deleteFile(String path) {
if (StringUtils.isBlank(path)) {
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
* <ul>
* <li>if path is null or empty, return -</li>
* <li>if path exist and it is a file, return file size, else return -</li>
* <ul>
*
* @param path
* @return returns the length of this file in bytes. returns - if the file does not exist.
*/
public static long getFileSize(String path) {
if (StringUtils.isBlank(path)) {
return -;
}
File file = new File(path);
return (file.exists() && file.isFile() ? file.length() : -);
}
}
十三、assets和raw资源工具类 ResourceUtils.java
? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111public class ResourceUtils {
private ResourceUtils() {
throw new AssertionError();
}
/**
* get an asset using ACCESS_STREAMING mode. This provides access to files that have been bundled with an
* application as assets -- that is, files placed in to the "assets" directory.
*
* @param context
* @param fileName The name of the asset to open. This name can be hierarchical.
* @return
*/
public static String geFileFromAssets(Context context, String fileName) {
if (context == null || StringUtils.isEmpty(fileName)) {
return null;
}
StringBuilder s = new StringBuilder("");
try {
InputStreamReader in = new InputStreamReader(context.getResources().getAssets().open(fileName));
BufferedReader br = new BufferedReader(in);
String line;
while ((line = br.readLine()) != null) {
s.append(line);
}
return s.toString();
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
/**
* get content from a raw resource. This can only be used with resources whose value is the name of an asset files
* -- that is, it can be used to open drawable, sound, and raw resources; it will fail on string and color
* resources.
*
* @param context
* @param resId The resource identifier to open, as generated by the appt tool.
* @return
*/
public static String geFileFromRaw(Context context, int resId) {
if (context == null) {
return null;
}
StringBuilder s = new StringBuilder();
try {
InputStreamReader in = new InputStreamReader(context.getResources().openRawResource(resId));
BufferedReader br = new BufferedReader(in);
String line;
while ((line = br.readLine()) != null) {
s.append(line);
}
return s.toString();
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
/**
* same to {@link ResourceUtils#geFileFromAssets(Context, String)}, but return type is List<String>
*
* @param context
* @param fileName
* @return
*/
public static List<String> geFileToListFromAssets(Context context, String fileName) {
if (context == null || StringUtils.isEmpty(fileName)) {
return null;
}
List<String> fileContent = new ArrayList<String>();
try {
InputStreamReader in = new InputStreamReader(context.getResources().getAssets().open(fileName));
BufferedReader br = new BufferedReader(in);
String line;
while ((line = br.readLine()) != null) {
fileContent.add(line);
}
br.close();
return fileContent;
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
/**
* same to {@link ResourceUtils#geFileFromRaw(Context, int)}, but return type is List<String>
*
* @param context
* @param resId
* @return
*/
public static List<String> geFileToListFromRaw(Context context, int resId) {
if (context == null) {
return null;
}
List<String> fileContent = new ArrayList<String>();
BufferedReader reader = null;
try {
InputStreamReader in = new InputStreamReader(context.getResources().openRawResource(resId));
reader = new BufferedReader(in);
String line = null;
while ((line = reader.readLine()) != null) {
fileContent.add(line);
}
reader.close();
return fileContent;
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
}
十四、单例工具类 SingletonUtils.java
? 1 2 3 4 5 6 7 8 9 10 11 12 13 14public abstract class SingletonUtils<T> {
private T instance;
protected abstract T newInstance();
public final T getInstance() {
if (instance == null) {
synchronized (SingletonUtils.class) {
if (instance == null) {
instance = newInstance();
}
}
}
return instance;
}
}
十五、数据库工具类 SqliteUtils.java
? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22public class SqliteUtils {
private static volatile SqliteUtils instance;
private DbHelper dbHelper;
private SQLiteDatabase db;
private SqliteUtils(Context context) {
dbHelper = new DbHelper(context);
db = dbHelper.getWritableDatabase();
}
public static SqliteUtils getInstance(Context context) {
if (instance == null) {
synchronized (SqliteUtils.class) {
if (instance == null) {
instance = new SqliteUtils(context);
}
}
}
return instance;
}
public SQLiteDatabase getDb() {
return db;
}
}
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