一、日志工具类 Log.java
1 public class L
2 {
3 private L()
4 {
5 /* 不可被实例化 */
6 throw new UnsupportedOperationException("Cannot be instantiated!");
7 }
8 // 是否需要打印bug，可以在application的onCreate函数里面初始化
9 public static boolean isDebug = true;
10 private static final String TAG = "DefaultTag";
11
12 // 下面四个是默认tag的函数
13 public static void i(String msg)
14 {
15 if (isDebug)
16 Log.i(TAG, msg);
17 }
18
19 public static void d(String msg)
20 {
21 if (isDebug)
22 Log.d(TAG, msg);
23 }
24
25 public static void e(String msg)
26 {
27 if (isDebug)
28 Log.e(TAG, msg);
29 }
30
31 public static void v(String msg)
32 {
33 if (isDebug)
34 Log.v(TAG, msg);
35 }
36
37 // 下面是传入自定义tag的函数
38 public static void i(String tag, String msg)
39 {
40 if (isDebug)
41 Log.i(tag, msg);
42 }
43
44 public static void d(String tag, String msg)
45 {
46 if (isDebug)
47 Log.i(tag, msg);
48 }
49
50 public static void e(String tag, String msg)
51 {
52 if (isDebug)
53 Log.i(tag, msg);
54 }
55
56 public static void v(String tag, String msg)
57 {
58 if (isDebug)
59 Log.i(tag, msg);
60 }
61 }
二、Toast统一管理类 Tost.java
public 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
1 public class SPUtils
2 {
3 /**
4 * 保存在手机里面的文件名
5 */
6 public static final String FILE_NAME = "share_data";
7
8 /**
9 * 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
10 *
11 * @param context
12 * @param key
13 * @param object
14 */
15 public static void put(Context context, String key, Object object)
16 {
17
18 SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
19 Context.MODE_PRIVATE);
20 SharedPreferences.Editor editor = sp.edit();
21
22 if (object instanceof String)
23 {
24 editor.putString(key, (String) object);
25 } else if (object instanceof Integer)
26 {
27 editor.putInt(key, (Integer) object);
28 } else if (object instanceof Boolean)
29 {
30 editor.putBoolean(key, (Boolean) object);
31 } else if (object instanceof Float)
32 {
33 editor.putFloat(key, (Float) object);
34 } else if (object instanceof Long)
35 {
36 editor.putLong(key, (Long) object);
37 } else
38 {
39 editor.putString(key, object.toString());
40 }
41
42 SharedPreferencesCompat.apply(editor);
43 }
44
45 /**
46 * 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
47 *
48 * @param context
49 * @param key
50 * @param defaultObject
51 * @return
52 */
53 public static Object get(Context context, String key, Object defaultObject)
54 {
55 SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
56 Context.MODE_PRIVATE);
57
58 if (defaultObject instanceof String)
59 {
60 return sp.getString(key, (String) defaultObject);
61 } else if (defaultObject instanceof Integer)
62 {
63 return sp.getInt(key, (Integer) defaultObject);
64 } else if (defaultObject instanceof Boolean)
65 {
66 return sp.getBoolean(key, (Boolean) defaultObject);
67 } else if (defaultObject instanceof Float)
68 {
69 return sp.getFloat(key, (Float) defaultObject);
70 } else if (defaultObject instanceof Long)
71 {
72 return sp.getLong(key, (Long) defaultObject);
73 }
74
75 return null;
76 }
77
78 /**
79 * 移除某个key值已经对应的值
80 * @param context
81 * @param key
82 */
83 public static void remove(Context context, String key)
84 {
85 SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
86 Context.MODE_PRIVATE);
87 SharedPreferences.Editor editor = sp.edit();
88 editor.remove(key);
89 SharedPreferencesCompat.apply(editor);
90 }
91
92 /**
93 * 清除所有数据
94 * @param context
95 */
96 public static void clear(Context context)
97 {
98 SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
99 Context.MODE_PRIVATE);
100 SharedPreferences.Editor editor = sp.edit();
101 editor.clear();
102 SharedPreferencesCompat.apply(editor);
103 }
104
105 /**
106 * 查询某个key是否已经存在
107 * @param context
108 * @param key
109 * @return
110 */
111 public static boolean contains(Context context, String key)
112 {
113 SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
114 Context.MODE_PRIVATE);
115 return sp.contains(key);
116 }
117
118 /**
119 * 返回所有的键值对
120 *
121 * @param context
122 * @return
123 */
124 public static Map<String, ?> getAll(Context context)
125 {
126 SharedPreferences sp = context.getSharedPreferences(FILE_NAME,
127 Context.MODE_PRIVATE);
128 return sp.getAll();
129 }
130
131 /**
132 * 创建一个解决SharedPreferencesCompat.apply方法的一个兼容类
133 *
134 * @author zhy
135 *
136 */
137 private static class SharedPreferencesCompat
138 {
139 private static final Method sApplyMethod = findApplyMethod();
140
141 /**
142 * 反射查找apply的方法
143 *
144 * @return
145 */
146 @SuppressWarnings({ "unchecked", "rawtypes" })
147 private static Method findApplyMethod()
148 {
149 try
150 {
151 Class clz = SharedPreferences.Editor.class;
152 return clz.getMethod("apply");
153 } catch (NoSuchMethodException e)
154 {
155 }
156
157 return null;
158 }
159
160 /**
161 * 如果找到则使用apply执行，否则使用commit
162 *
163 * @param editor
164 */
165 public static void apply(SharedPreferences.Editor editor)
166 {
167 try
168 {
169 if (sApplyMethod != null)
170 {
171 sApplyMethod.invoke(editor);
172 return;
173 }
174 } catch (IllegalArgumentException e)
175 {
176 } catch (IllegalAccessException e)
177 {
178 } catch (InvocationTargetException e)
179 {
180 }
181 editor.commit();
182 }
183 }
184
185 }
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
1 public class PreferencesUtils {
2
3 public static String PREFERENCE_NAME = "TrineaAndroidCommon";
4
5 private PreferencesUtils() {
6 throw new AssertionError();
7 }
8
9 /**
10 * put string preferences
11 *
12 * @param context
13 * @param key The name of the preference to modify
14 * @param value The new value for the preference
15 * @return True if the new values were successfully written to persistent storage.
16 */
17 public static boolean putString(Context context, String key, String value) {
18 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
19 SharedPreferences.Editor editor = settings.edit();
20 editor.putString(key, value);
21 return editor.commit();
22 }
23
24 /**
25 * get string preferences
26 *
27 * @param context
28 * @param key The name of the preference to retrieve
29 * @return The preference value if it exists, or null. Throws ClassCastException if there is a preference with this
30 * name that is not a string
31 * @see #getString(Context, String, String)
32 */
33 public static String getString(Context context, String key) {
34 return getString(context, key, null);
35 }
36
37 /**
38 * get string preferences
39 *
40 * @param context
41 * @param key The name of the preference to retrieve
42 * @param defaultValue Value to return if this preference does not exist
43 * @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with
44 * this name that is not a string
45 */
46 public static String getString(Context context, String key, String defaultValue) {
47 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
48 return settings.getString(key, defaultValue);
49 }
50
51 /**
52 * put int preferences
53 *
54 * @param context
55 * @param key The name of the preference to modify
56 * @param value The new value for the preference
57 * @return True if the new values were successfully written to persistent storage.
58 */
59 public static boolean putInt(Context context, String key, int value) {
60 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
61 SharedPreferences.Editor editor = settings.edit();
62 editor.putInt(key, value);
63 return editor.commit();
64 }
65
66 /**
67 * get int preferences
68 *
69 * @param context
70 * @param key The name of the preference to retrieve
71 * @return The preference value if it exists, or -1. Throws ClassCastException if there is a preference with this
72 * name that is not a int
73 * @see #getInt(Context, String, int)
74 */
75 public static int getInt(Context context, String key) {
76 return getInt(context, key, -1);
77 }
78
79 /**
80 * get int preferences
81 *
82 * @param context
83 * @param key The name of the preference to retrieve
84 * @param defaultValue Value to return if this preference does not exist
85 * @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with
86 * this name that is not a int
87 */
88 public static int getInt(Context context, String key, int defaultValue) {
89 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
90 return settings.getInt(key, defaultValue);
91 }
92
93 /**
94 * put long preferences
95 *
96 * @param context
97 * @param key The name of the preference to modify
98 * @param value The new value for the preference
99 * @return True if the new values were successfully written to persistent storage.
100 */
101 public static boolean putLong(Context context, String key, long value) {
102 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
103 SharedPreferences.Editor editor = settings.edit();
104 editor.putLong(key, value);
105 return editor.commit();
106 }
107
108 /**
109 * get long preferences
110 *
111 * @param context
112 * @param key The name of the preference to retrieve
113 * @return The preference value if it exists, or -1. Throws ClassCastException if there is a preference with this
114 * name that is not a long
115 * @see #getLong(Context, String, long)
116 */
117 public static long getLong(Context context, String key) {
118 return getLong(context, key, -1);
119 }
120
121 /**
122 * get long preferences
123 *
124 * @param context
125 * @param key The name of the preference to retrieve
126 * @param defaultValue Value to return if this preference does not exist
127 * @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with
128 * this name that is not a long
129 */
130 public static long getLong(Context context, String key, long defaultValue) {
131 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
132 return settings.getLong(key, defaultValue);
133 }
134
135 /**
136 * put float preferences
137 *
138 * @param context
139 * @param key The name of the preference to modify
140 * @param value The new value for the preference
141 * @return True if the new values were successfully written to persistent storage.
142 */
143 public static boolean putFloat(Context context, String key, float value) {
144 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
145 SharedPreferences.Editor editor = settings.edit();
146 editor.putFloat(key, value);
147 return editor.commit();
148 }
149
150 /**
151 * get float preferences
152 *
153 * @param context
154 * @param key The name of the preference to retrieve
155 * @return The preference value if it exists, or -1. Throws ClassCastException if there is a preference with this
156 * name that is not a float
157 * @see #getFloat(Context, String, float)
158 */
159 public static float getFloat(Context context, String key) {
160 return getFloat(context, key, -1);
161 }
162
163 /**
164 * get float preferences
165 *
166 * @param context
167 * @param key The name of the preference to retrieve
168 * @param defaultValue Value to return if this preference does not exist
169 * @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with
170 * this name that is not a float
171 */
172 public static float getFloat(Context context, String key, float defaultValue) {
173 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
174 return settings.getFloat(key, defaultValue);
175 }
176
177 /**
178 * put boolean preferences
179 *
180 * @param context
181 * @param key The name of the preference to modify
182 * @param value The new value for the preference
183 * @return True if the new values were successfully written to persistent storage.
184 */
185 public static boolean putBoolean(Context context, String key, boolean value) {
186 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
187 SharedPreferences.Editor editor = settings.edit();
188 editor.putBoolean(key, value);
189 return editor.commit();
190 }
191
192 /**
193 * get boolean preferences, default is false
194 *
195 * @param context
196 * @param key The name of the preference to retrieve
197 * @return The preference value if it exists, or false. Throws ClassCastException if there is a preference with this
198 * name that is not a boolean
199 * @see #getBoolean(Context, String, boolean)
200 */
201 public static boolean getBoolean(Context context, String key) {
202 return getBoolean(context, key, false);
203 }
204
205 /**
206 * get boolean preferences
207 *
208 * @param context
209 * @param key The name of the preference to retrieve
210 * @param defaultValue Value to return if this preference does not exist
211 * @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with
212 * this name that is not a boolean
213 */
214 public static boolean getBoolean(Context context, String key, boolean defaultValue) {
215 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
216 return settings.getBoolean(key, defaultValue);
217 }
218 }
四、单位转换类 DensityUtils.java
1 public class DensityUtils
2 {
3 private DensityUtils()
4 {
5 /* cannot be instantiated */
6 throw new UnsupportedOperationException("cannot be instantiated");
7 }
8
9 /**
10 * dp转px
11 *
12 * @param context
13 * @param val
14 * @return
15 */
16 public static int dp2px(Context context, float dpVal)
17 {
18 return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
19 dpVal, context.getResources().getDisplayMetrics());
20 }
21
22 /**
23 * sp转px
24 *
25 * @param context
26 * @param val
27 * @return
28 */
29 public static int sp2px(Context context, float spVal)
30 {
31 return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP,
32 spVal, context.getResources().getDisplayMetrics());
33 }
34
35 /**
36 * px转dp
37 *
38 * @param context
39 * @param pxVal
40 * @return
41 */
42 public static float px2dp(Context context, float pxVal)
43 {
44 final float scale = context.getResources().getDisplayMetrics().density;
45 return (pxVal / scale);
46 }
47
48 /**
49 * px转sp
50 *
51 * @param fontScale
52 * @param pxVal
53 * @return
54 */
55 public static float px2sp(Context context, float pxVal)
56 {
57 return (pxVal / context.getResources().getDisplayMetrics().scaledDensity);
58 }
59
60 }
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
1 public class SDCardUtils
2 {
3 private SDCardUtils()
4 {
5 /* cannot be instantiated */
6 throw new UnsupportedOperationException("cannot be instantiated");
7 }
8
9 /**
10 * 判断SDCard是否可用
11 *
12 * @return
13 */
14 public static boolean isSDCardEnable()
15 {
16 return Environment.getExternalStorageState().equals(
17 Environment.MEDIA_MOUNTED);
18
19 }
20
21 /**
22 * 获取SD卡路径
23 *
24 * @return
25 */
26 public static String getSDCardPath()
27 {
28 return Environment.getExternalStorageDirectory().getAbsolutePath()
29 + File.separator;
30 }
31
32 /**
33 * 获取SD卡的剩余容量 单位byte
34 *
35 * @return
36 */
37 public static long getSDCardAllSize()
38 {
39 if (isSDCardEnable())
40 {
41 StatFs stat = new StatFs(getSDCardPath());
42 // 获取空闲的数据块的数量
43 long availableBlocks = (long) stat.getAvailableBlocks() - 4;
44 // 获取单个数据块的大小（byte）
45 long freeBlocks = stat.getAvailableBlocks();
46 return freeBlocks * availableBlocks;
47 }
48 return 0;
49 }
50
51 /**
52 * 获取指定路径所在空间的剩余可用容量字节数，单位byte
53 *
54 * @param filePath
55 * @return 容量字节 SDCard可用空间，内部存储可用空间
56 */
57 public static long getFreeBytes(String filePath)
58 {
59 // 如果是sd卡的下的路径，则获取sd卡可用容量
60 if (filePath.startsWith(getSDCardPath()))
61 {
62 filePath = getSDCardPath();
63 } else
64 {// 如果是内部存储的路径，则获取内存存储的可用容量
65 filePath = Environment.getDataDirectory().getAbsolutePath();
66 }
67 StatFs stat = new StatFs(filePath);
68 long availableBlocks = (long) stat.getAvailableBlocks() - 4;
69 return stat.getBlockSize() * availableBlocks;
70 }
71
72 /**
73 * 获取系统存储路径
74 *
75 * @return
76 */
77 public static String getRootDirectoryPath()
78 {
79 return Environment.getRootDirectory().getAbsolutePath();
80 }
81
82 }
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 public class ScreenUtils
2 {
3 private ScreenUtils()
4 {
5 /* cannot be instantiated */
6 throw new UnsupportedOperationException("cannot be instantiated");
7 }
8
9 /**
10 * 获得屏幕高度
11 *
12 * @param context
13 * @return
14 */
15 public static int getScreenWidth(Context context)
16 {
17 WindowManager wm = (WindowManager) context
18 .getSystemService(Context.WINDOW_SERVICE);
19 DisplayMetrics outMetrics = new DisplayMetrics();
20 wm.getDefaultDisplay().getMetrics(outMetrics);
21 return outMetrics.widthPixels;
22 }
23
24 /**
25 * 获得屏幕宽度
26 *
27 * @param context
28 * @return
29 */
30 public static int getScreenHeight(Context context)
31 {
32 WindowManager wm = (WindowManager) context
33 .getSystemService(Context.WINDOW_SERVICE);
34 DisplayMetrics outMetrics = new DisplayMetrics();
35 wm.getDefaultDisplay().getMetrics(outMetrics);
36 return outMetrics.heightPixels;
37 }
38
39 /**
40 * 获得状态栏的高度
41 *
42 * @param context
43 * @return
44 */
45 public static int getStatusHeight(Context context)
46 {
47
48 int statusHeight = -1;
49 try
50 {
51 Class<?> clazz = Class.forName("com.android.internal.R$dimen");
52 Object object = clazz.newInstance();
53 int height = Integer.parseInt(clazz.getField("status_bar_height")
54 .get(object).toString());
55 statusHeight = context.getResources().getDimensionPixelSize(height);
56 } catch (Exception e)
57 {
58 e.printStackTrace();
59 }
60 return statusHeight;
61 }
62
63 /**
64 * 获取当前屏幕截图，包含状态栏
65 *
66 * @param activity
67 * @return
68 */
69 public static Bitmap snapShotWithStatusBar(Activity activity)
70 {
71 View view = activity.getWindow().getDecorView();
72 view.setDrawingCacheEnabled(true);
73 view.buildDrawingCache();
74 Bitmap bmp = view.getDrawingCache();
75 int width = getScreenWidth(activity);
76 int height = getScreenHeight(activity);
77 Bitmap bp = null;
78 bp = Bitmap.createBitmap(bmp, 0, 0, width, height);
79 view.destroyDrawingCache();
80 return bp;
81
82 }
83
84 /**
85 * 获取当前屏幕截图，不包含状态栏
86 *
87 * @param activity
88 * @return
89 */
90 public static Bitmap snapShotWithoutStatusBar(Activity activity)
91 {
92 View view = activity.getWindow().getDecorView();
93 view.setDrawingCacheEnabled(true);
94 view.buildDrawingCache();
95 Bitmap bmp = view.getDrawingCache();
96 Rect frame = new Rect();
97 activity.getWindow().getDecorView().getWindowVisibleDisplayFrame(frame);
98 int statusBarHeight = frame.top;
99
100 int width = getScreenWidth(activity);
101 int height = getScreenHeight(activity);
102 Bitmap bp = null;
103 bp = Bitmap.createBitmap(bmp, 0, statusBarHeight, width, height
104 - statusBarHeight);
105 view.destroyDrawingCache();
106 return bp;
107
108 }
109
110 }
七、App相关辅助类 APPUtils.java
1 public class AppUtils
2 {
3 private AppUtils()
4 {
5 /* cannot be instantiated */
6 throw new UnsupportedOperationException("cannot be instantiated");
7 }
8
9 /**
10 * 获取应用程序名称
11 */
12 public static String getAppName(Context context)
13 {
14 try
15 {
16 PackageManager packageManager = context.getPackageManager();
17 PackageInfo packageInfo = packageManager.getPackageInfo(
18 context.getPackageName(), 0);
19 int labelRes = packageInfo.applicationInfo.labelRes;
20 return context.getResources().getString(labelRes);
21 } catch (NameNotFoundException e)
22 {
23 e.printStackTrace();
24 }
25 return null;
26 }
27
28 /**
29 * [获取应用程序版本名称信息]
30 *
31 * @param context
32 * @return 当前应用的版本名称
33 */
34 public static String getVersionName(Context context)
35 {
36 try
37 {
38 PackageManager packageManager = context.getPackageManager();
39 PackageInfo packageInfo = packageManager.getPackageInfo(
40 context.getPackageName(), 0);
41 return packageInfo.versionName;
42
43 } catch (NameNotFoundException e)
44 {
45 e.printStackTrace();
46 }
47 return null;
48 }
49
50 }
八、软键盘相关辅助类KeyBoardUtils.java
1 /**
2 * 打开或关闭软键盘
3 */
4 public class KeyBoardUtils
5 {
6 /**
7 * 打卡软键盘
8 *
9 * @param mEditText 输入框
10 * @param mContext 上下文
11 */
12 public static void openKeybord(EditText mEditText, Context mContext)
13 {
14 InputMethodManager imm = (InputMethodManager) mContext
15 .getSystemService(Context.INPUT_METHOD_SERVICE);
16 imm.showSoftInput(mEditText, InputMethodManager.RESULT_SHOWN);
17 imm.toggleSoftInput(InputMethodManager.SHOW_FORCED,
18 InputMethodManager.HIDE_IMPLICIT_ONLY);
19 }
20
21 /**
22 * 关闭软键盘
23 *
24 * @param mEditText 输入框
25 * @param mContext 上下文
26 */
27 public static void closeKeybord(EditText mEditText, Context mContext)
28 {
29 InputMethodManager imm = (InputMethodManager) mContext
30 .getSystemService(Context.INPUT_METHOD_SERVICE);
31 imm.hideSoftInputFromWindow(mEditText.getWindowToken(), 0);
32 }
33 }
九、网络相关辅助类 NetUtils.java
1 public class NetUtils
2 {
3 private NetUtils()
4 {
5 /* cannot be instantiated */
6 throw new UnsupportedOperationException("cannot be instantiated");
7 }
8
9 /**
10 * 判断网络是否连接
11 */
12 public static boolean isConnected(Context context)
13 {
14 ConnectivityManager connectivity = (ConnectivityManager) context
15 .getSystemService(Context.CONNECTIVITY_SERVICE);
16
17 if (null != connectivity)
18 {
19 NetworkInfo info = connectivity.getActiveNetworkInfo();
20 if (null != info && info.isConnected())
21 {
22 if (info.getState() == NetworkInfo.State.CONNECTED)
23 {
24 return true;
25 }
26 }
27 }
28 return false;
29 }
30
31 /**
32 * 判断是否是wifi连接
33 */
34 public static boolean isWifi(Context context)
35 {
36 ConnectivityManager cm = (ConnectivityManager) context
37 .getSystemService(Context.CONNECTIVITY_SERVICE);
38
39 if (cm == null)
40 return false;
41 return cm.getActiveNetworkInfo().getType() == ConnectivityManager.TYPE_WIFI;
42
43 }
44
45 /**
46 * 打开网络设置界面
47 */
48 public static void openSetting(Activity activity)
49 {
50 Intent intent = new Intent("/");
51 ComponentName cm = new ComponentName("com.android.settings",
52 "com.android.settings.WirelessSettings");
53 intent.setComponent(cm);
54 intent.setAction("android.intent.action.VIEW");
55 activity.startActivityForResult(intent, 0);
56 }
57
58 }
十、Http相关辅助类 HttpUtils.java
1 /**
2 * Http请求的工具类
3 */
4 public class HttpUtils
5 {
6 private static final int TIMEOUT_IN_MILLIONS = 5000;
7
8 public interface CallBack
9 {
10 void onRequestComplete(String result);
11 }
12
13
14 /**
15 * 异步的Get请求
16 *
17 * @param urlStr
18 * @param callBack
19 */
20 public static void doGetAsyn(final String urlStr, final CallBack callBack)
21 {
22 new Thread()
23 {
24 public void run()
25 {
26 try
27 {
28 String result = doGet(urlStr);
29 if (callBack != null)
30 {
31 callBack.onRequestComplete(result);
32 }
33 } catch (Exception e)
34 {
35 e.printStackTrace();
36 }
37
38 };
39 }.start();
40 }
41
42 /**
43 * 异步的Post请求
44 * @param urlStr
45 * @param params
46 * @param callBack
47 * @throws Exception
48 */
49 public static void doPostAsyn(final String urlStr, final String params,
50 final CallBack callBack) throws Exception
51 {
52 new Thread()
53 {
54 public void run()
55 {
56 try
57 {
58 String result = doPost(urlStr, params);
59 if (callBack != null)
60 {
61 callBack.onRequestComplete(result);
62 }
63 } catch (Exception e)
64 {
65 e.printStackTrace();
66 }
67
68 };
69 }.start();
70
71 }
72
73 /**
74 * Get请求，获得返回数据
75 *
76 * @param urlStr
77 * @return
78 * @throws Exception
79 */
80 public static String doGet(String urlStr)
81 {
82 URL url = null;
83 HttpURLConnection conn = null;
84 InputStream is = null;
85 ByteArrayOutputStream baos = null;
86 try
87 {
88 url = new URL(urlStr);
89 conn = (HttpURLConnection) url.openConnection();
90 conn.setReadTimeout(TIMEOUT_IN_MILLIONS);
91 conn.setConnectTimeout(TIMEOUT_IN_MILLIONS);
92 conn.setRequestMethod("GET");
93 conn.setRequestProperty("accept", "*/*");
94 conn.setRequestProperty("connection", "Keep-Alive");
95 if (conn.getResponseCode() == 200)
96 {
97 is = conn.getInputStream();
98 baos = new ByteArrayOutputStream();
99 int len = -1;
100 byte[] buf = new byte[128];
101
102 while ((len = is.read(buf)) != -1)
103 {
104 baos.write(buf, 0, len);
105 }
106 baos.flush();
107 return baos.toString();
108 } else
109 {
110 throw new RuntimeException(" responseCode is not 200 ... ");
111 }
112
113 } catch (Exception e)
114 {
115 e.printStackTrace();
116 } finally
117 {
118 try
119 {
120 if (is != null)
121 is.close();
122 } catch (IOException e)
123 {
124 }
125 try
126 {
127 if (baos != null)
128 baos.close();
129 } catch (IOException e)
130 {
131 }
132 conn.disconnect();
133 }
134
135 return null ;
136
137 }
138
139 /**
140 * 向指定 URL 发送POST方法的请求
141 *
142 * @param url
143 * 发送请求的 URL
144 * @param param
145 * 请求参数，请求参数应该是 name1=value1&name2=value2 的形式。
146 * @return 所代表远程资源的响应结果
147 * @throws Exception
148 */
149 public static String doPost(String url, String param)
150 {
151 PrintWriter out = null;
152 BufferedReader in = null;
153 String result = "";
154 try
155 {
156 URL realUrl = new URL(url);
157 // 打开和URL之间的连接
158 HttpURLConnection conn = (HttpURLConnection) realUrl
159 .openConnection();
160 // 设置通用的请求属性
161 conn.setRequestProperty("accept", "*/*");
162 conn.setRequestProperty("connection", "Keep-Alive");
163 conn.setRequestMethod("POST");
164 conn.setRequestProperty("Content-Type",
165 "application/x-www-form-urlencoded");
166 conn.setRequestProperty("charset", "utf-8");
167 conn.setUseCaches(false);
168 // 发送POST请求必须设置如下两行
169 conn.setDoOutput(true);
170 conn.setDoInput(true);
171 conn.setReadTimeout(TIMEOUT_IN_MILLIONS);
172 conn.setConnectTimeout(TIMEOUT_IN_MILLIONS);
173
174 if (param != null && !param.trim().equals(""))
175 {
176 // 获取URLConnection对象对应的输出流
177 out = new PrintWriter(conn.getOutputStream());
178 // 发送请求参数
179 out.print(param);
180 // flush输出流的缓冲
181 out.flush();
182 }
183 // 定义BufferedReader输入流来读取URL的响应
184 in = new BufferedReader(
185 new InputStreamReader(conn.getInputStream()));
186 String line;
187 while ((line = in.readLine()) != null)
188 {
189 result += line;
190 }
191 } catch (Exception e)
192 {
193 e.printStackTrace();
194 }
195 // 使用finally块来关闭输出流、输入流
196 finally
197 {
198 try
199 {
200 if (out != null)
201 {
202 out.close();
203 }
204 if (in != null)
205 {
206 in.close();
207 }
208 } catch (IOException ex)
209 {
210 ex.printStackTrace();
211 }
212 }
213 return result;
214 }
215 }
十一、时间工具类 TimeUtils.java
1 public class TimeUtils {
2
3 public static final SimpleDateFormat DEFAULT_DATE_FORMAT =
4 new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
5 public static final SimpleDateFormat DATE_FORMAT_DATE =
6 new SimpleDateFormat("yyyy-MM-dd");
7
8 private TimeUtils() {
9 throw new AssertionError();
10 }
11
12 /**
13 * long time to string
14 *
15 * @param timeInMillis
16 * @param dateFormat
17 * @return
18 */
19 public static String getTime(long timeInMillis, SimpleDateFormat dateFormat) {
20 return dateFormat.format(new Date(timeInMillis));
21 }
22
23 /**
24 * long time to string, format is {@link #DEFAULT_DATE_FORMAT}
25 *
26 * @param timeInMillis
27 * @return
28 */
29 public static String getTime(long timeInMillis) {
30 return getTime(timeInMillis, DEFAULT_DATE_FORMAT);
31 }
32
33 /**
34 * get current time in milliseconds
35 *
36 * @return
37 */
38 public static long getCurrentTimeInLong() {
39 return System.currentTimeMillis();
40 }
41
42 /**
43 * get current time in milliseconds, format is {@link #DEFAULT_DATE_FORMAT}
44 *
45 * @return
46 */
47 public static String getCurrentTimeInString() {
48 return getTime(getCurrentTimeInLong());
49 }
50
51 /**
52 * get current time in milliseconds
53 *
54 * @return
55 */
56 public static String getCurrentTimeInString(SimpleDateFormat dateFormat) {
57 return getTime(getCurrentTimeInLong(), dateFormat);
58 }
59 }
十二、文件工具类 FileUtils.java
1 public class FileUtils {
2
3 public final static String FILE_EXTENSION_SEPARATOR = ".";
4
5 private FileUtils() {
6 throw new AssertionError();
7 }
8
9 /**
10 * read file
11 *
12 * @param filePath
13 * @param charsetName The name of a supported {@link java.nio.charset.Charset </code>charset<code>}
14 * @return if file not exist, return null, else return content of file
15 * @throws RuntimeException if an error occurs while operator BufferedReader
16 */
17 public static StringBuilder readFile(String filePath, String charsetName) {
18 File file = new File(filePath);
19 StringBuilder fileContent = new StringBuilder("");
20 if (file == null || !file.isFile()) {
21 return null;
22 }
23
24 BufferedReader reader = null;
25 try {
26 InputStreamReader is = new InputStreamReader(new FileInputStream(file), charsetName);
27 reader = new BufferedReader(is);
28 String line = null;
29 while ((line = reader.readLine()) != null) {
30 if (!fileContent.toString().equals("")) {
31 fileContent.append("\r\n");
32 }
33 fileContent.append(line);
34 }
35 return fileContent;
36 } catch (IOException e) {
37 throw new RuntimeException("IOException occurred. ", e);
38 } finally {
39 IOUtils.close(reader);
40 }
41 }
42
43 /**
44 * write file
45 *
46 * @param filePath
47 * @param content
48 * @param append is append, if true, write to the end of file, else clear content of file and write into it
49 * @return return false if content is empty, true otherwise
50 * @throws RuntimeException if an error occurs while operator FileWriter
51 */
52 public static boolean writeFile(String filePath, String content, boolean append) {
53 if (StringUtils.isEmpty(content)) {
54 return false;
55 }
56
57 FileWriter fileWriter = null;
58 try {
59 makeDirs(filePath);
60 fileWriter = new FileWriter(filePath, append);
61 fileWriter.write(content);
62 return true;
63 } catch (IOException e) {
64 throw new RuntimeException("IOException occurred. ", e);
65 } finally {
66 IOUtils.close(fileWriter);
67 }
68 }
69
70 /**
71 * write file
72 *
73 * @param filePath
74 * @param contentList
75 * @param append is append, if true, write to the end of file, else clear content of file and write into it
76 * @return return false if contentList is empty, true otherwise
77 * @throws RuntimeException if an error occurs while operator FileWriter
78 */
79 public static boolean writeFile(String filePath, List<String> contentList, boolean append) {
80 if (ListUtils.isEmpty(contentList)) {
81 return false;
82 }
83
84 FileWriter fileWriter = null;
85 try {
86 makeDirs(filePath);
87 fileWriter = new FileWriter(filePath, append);
88 int i = 0;
89 for (String line : contentList) {
90 if (i++ > 0) {
91 fileWriter.write("\r\n");
92 }
93 fileWriter.write(line);
94 }
95 return true;
96 } catch (IOException e) {
97 throw new RuntimeException("IOException occurred. ", e);
98 } finally {
99 IOUtils.close(fileWriter);
100 }
101 }
102
103 /**
104 * write file, the string will be written to the begin of the file
105 *
106 * @param filePath
107 * @param content
108 * @return
109 */
110 public static boolean writeFile(String filePath, String content) {
111 return writeFile(filePath, content, false);
112 }
113
114 /**
115 * write file, the string list will be written to the begin of the file
116 *
117 * @param filePath
118 * @param contentList
119 * @return
120 */
121 public static boolean writeFile(String filePath, List<String> contentList) {
122 return writeFile(filePath, contentList, false);
123 }
124
125 /**
126 * write file, the bytes will be written to the begin of the file
127 *
128 * @param filePath
129 * @param stream
130 * @return
131 * @see {@link #writeFile(String, InputStream, boolean)}
132 */
133 public static boolean writeFile(String filePath, InputStream stream) {
134 return writeFile(filePath, stream, false);
135 }
136
137 /**
138 * write file
139 *
140 * @param file the file to be opened for writing.
141 * @param stream the input stream
142 * @param append if <code>true</code>, then bytes will be written to the end of the file rather than the beginning
143 * @return return true
144 * @throws RuntimeException if an error occurs while operator FileOutputStream
145 */
146 public static boolean writeFile(String filePath, InputStream stream, boolean append) {
147 return writeFile(filePath != null ? new File(filePath) : null, stream, append);
148 }
149
150 /**
151 * write file, the bytes will be written to the begin of the file
152 *
153 * @param file
154 * @param stream
155 * @return
156 * @see {@link #writeFile(File, InputStream, boolean)}
157 */
158 public static boolean writeFile(File file, InputStream stream) {
159 return writeFile(file, stream, false);
160 }
161
162 /**
163 * write file
164 *
165 * @param file the file to be opened for writing.
166 * @param stream the input stream
167 * @param append if <code>true</code>, then bytes will be written to the end of the file rather than the beginning
168 * @return return true
169 * @throws RuntimeException if an error occurs while operator FileOutputStream
170 */
171 public static boolean writeFile(File file, InputStream stream, boolean append) {
172 OutputStream o = null;
173 try {
174 makeDirs(file.getAbsolutePath());
175 o = new FileOutputStream(file, append);
176 byte data[] = new byte[1024];
177 int length = -1;
178 while ((length = stream.read(data)) != -1) {
179 o.write(data, 0, length);
180 }
181 o.flush();
182 return true;
183 } catch (FileNotFoundException e) {
184 throw new RuntimeException("FileNotFoundException occurred. ", e);
185 } catch (IOException e) {
186 throw new RuntimeException("IOException occurred. ", e);
187 } finally {
188 IOUtils.close(o);
189 IOUtils.close(stream);
190 }
191 }
192
193 /**
194 * move file
195 *
196 * @param sourceFilePath
197 * @param destFilePath
198 */
199 public static void moveFile(String sourceFilePath, String destFilePath) {
200 if (TextUtils.isEmpty(sourceFilePath) || TextUtils.isEmpty(destFilePath)) {
201 throw new RuntimeException("Both sourceFilePath and destFilePath cannot be null.");
202 }
203 moveFile(new File(sourceFilePath), new File(destFilePath));
204 }
205
206 /**
207 * move file
208 *
209 * @param srcFile
210 * @param destFile
211 */
212 public static void moveFile(File srcFile, File destFile) {
213 boolean rename = srcFile.renameTo(destFile);
214 if (!rename) {
215 copyFile(srcFile.getAbsolutePath(), destFile.getAbsolutePath());
216 deleteFile(srcFile.getAbsolutePath());
217 }
218 }
219
220 /**
221 * copy file
222 *
223 * @param sourceFilePath
224 * @param destFilePath
225 * @return
226 * @throws RuntimeException if an error occurs while operator FileOutputStream
227 */
228 public static boolean copyFile(String sourceFilePath, String destFilePath) {
229 InputStream inputStream = null;
230 try {
231 inputStream = new FileInputStream(sourceFilePath);
232 } catch (FileNotFoundException e) {
233 throw new RuntimeException("FileNotFoundException occurred. ", e);
234 }
235 return writeFile(destFilePath, inputStream);
236 }
237
238 /**
239 * read file to string list, a element of list is a line
240 *
241 * @param filePath
242 * @param charsetName The name of a supported {@link java.nio.charset.Charset </code>charset<code>}
243 * @return if file not exist, return null, else return content of file
244 * @throws RuntimeException if an error occurs while operator BufferedReader
245 */
246 public static List<String> readFileToList(String filePath, String charsetName) {
247 File file = new File(filePath);
248 List<String> fileContent = new ArrayList<String>();
249 if (file == null || !file.isFile()) {
250 return null;
251 }
252
253 BufferedReader reader = null;
254 try {
255 InputStreamReader is = new InputStreamReader(new FileInputStream(file), charsetName);
256 reader = new BufferedReader(is);
257 String line = null;
258 while ((line = reader.readLine()) != null) {
259 fileContent.add(line);
260 }
261 return fileContent;
262 } catch (IOException e) {
263 throw new RuntimeException("IOException occurred. ", e);
264 } finally {
265 IOUtils.close(reader);
266 }
267 }
268
269 /**
270 * get file name from path, not include suffix
271 *
272 * <pre>
273 * getFileNameWithoutExtension(null) = null
274 * getFileNameWithoutExtension("") = ""
275 * getFileNameWithoutExtension(" ") = " "
276 * getFileNameWithoutExtension("abc") = "abc"
277 * getFileNameWithoutExtension("a.mp3") = "a"
278 * getFileNameWithoutExtension("a.b.rmvb") = "a.b"
279 * getFileNameWithoutExtension("c:\\") = ""
280 * getFileNameWithoutExtension("c:\\a") = "a"
281 * getFileNameWithoutExtension("c:\\a.b") = "a"
282 * getFileNameWithoutExtension("c:a.txt\\a") = "a"
283 * getFileNameWithoutExtension("/home/admin") = "admin"
284 * getFileNameWithoutExtension("/home/admin/a.txt/b.mp3") = "b"
285 * </pre>
286 *
287 * @param filePath
288 * @return file name from path, not include suffix
289 * @see
290 */
291 public static String getFileNameWithoutExtension(String filePath) {
292 if (StringUtils.isEmpty(filePath)) {
293 return filePath;
294 }
295
296 int extenPosi = filePath.lastIndexOf(FILE_EXTENSION_SEPARATOR);
297 int filePosi = filePath.lastIndexOf(File.separator);
298 if (filePosi == -1) {
299 return (extenPosi == -1 ? filePath : filePath.substring(0, extenPosi));
300 }
301 if (extenPosi == -1) {
302 return filePath.substring(filePosi + 1);
303 }
304 return (filePosi < extenPosi ? filePath.substring(filePosi + 1, extenPosi) : filePath.substring(filePosi + 1));
305 }
306
307 /**
308 * get file name from path, include suffix
309 *
310 * <pre>
311 * getFileName(null) = null
312 * getFileName("") = ""
313 * getFileName(" ") = " "
314 * getFileName("a.mp3") = "a.mp3"
315 * getFileName("a.b.rmvb") = "a.b.rmvb"
316 * getFileName("abc") = "abc"
317 * getFileName("c:\\") = ""
318 * getFileName("c:\\a") = "a"
319 * getFileName("c:\\a.b") = "a.b"
320 * getFileName("c:a.txt\\a") = "a"
321 * getFileName("/home/admin") = "admin"
322 * getFileName("/home/admin/a.txt/b.mp3") = "b.mp3"
323 * </pre>
324 *
325 * @param filePath
326 * @return file name from path, include suffix
327 */
328 public static String getFileName(String filePath) {
329 if (StringUtils.isEmpty(filePath)) {
330 return filePath;
331 }
332
333 int filePosi = filePath.lastIndexOf(File.separator);
334 return (filePosi == -1) ? filePath : filePath.substring(filePosi + 1);
335 }
336
337 /**
338 * get folder name from path
339 *
340 * <pre>
341 * getFolderName(null) = null
342 * getFolderName("") = ""
343 * getFolderName(" ") = ""
344 * getFolderName("a.mp3") = ""
345 * getFolderName("a.b.rmvb") = ""
346 * getFolderName("abc") = ""
347 * getFolderName("c:\\") = "c:"
348 * getFolderName("c:\\a") = "c:"
349 * getFolderName("c:\\a.b") = "c:"
350 * getFolderName("c:a.txt\\a") = "c:a.txt"
351 * getFolderName("c:a\\b\\c\\d.txt") = "c:a\\b\\c"
352 * getFolderName("/home/admin") = "/home"
353 * getFolderName("/home/admin/a.txt/b.mp3") = "/home/admin/a.txt"
354 * </pre>
355 *
356 * @param filePath
357 * @return
358 */
359 public static String getFolderName(String filePath) {
360
361 if (StringUtils.isEmpty(filePath)) {
362 return filePath;
363 }
364
365 int filePosi = filePath.lastIndexOf(File.separator);
366 return (filePosi == -1) ? "" : filePath.substring(0, filePosi);
367 }
368
369 /**
370 * get suffix of file from path
371 *
372 * <pre>
373 * getFileExtension(null) = ""
374 * getFileExtension("") = ""
375 * getFileExtension(" ") = " "
376 * getFileExtension("a.mp3") = "mp3"
377 * getFileExtension("a.b.rmvb") = "rmvb"
378 * getFileExtension("abc") = ""
379 * getFileExtension("c:\\") = ""
380 * getFileExtension("c:\\a") = ""
381 * getFileExtension("c:\\a.b") = "b"
382 * getFileExtension("c:a.txt\\a") = ""
383 * getFileExtension("/home/admin") = ""
384 * getFileExtension("/home/admin/a.txt/b") = ""
385 * getFileExtension("/home/admin/a.txt/b.mp3") = "mp3"
386 * </pre>
387 *
388 * @param filePath
389 * @return
390 */
391 public static String getFileExtension(String filePath) {
392 if (StringUtils.isBlank(filePath)) {
393 return filePath;
394 }
395
396 int extenPosi = filePath.lastIndexOf(FILE_EXTENSION_SEPARATOR);
397 int filePosi = filePath.lastIndexOf(File.separator);
398 if (extenPosi == -1) {
399 return "";
400 }
401 return (filePosi >= extenPosi) ? "" : filePath.substring(extenPosi + 1);
402 }
403
404 /**
405 * Creates the directory named by the trailing filename of this file, including the complete directory path required
406 * to create this directory. <br/>
407 * <br/>
408 * <ul>
409 * <strong>Attentions:</strong>
410 * <li>makeDirs("C:\\Users\\Trinea") can only create users folder</li>
411 * <li>makeFolder("C:\\Users\\Trinea\\") can create Trinea folder</li>
412 * </ul>
413 *
414 * @param filePath
415 * @return true if the necessary directories have been created or the target directory already exists, false one of
416 * the directories can not be created.
417 * <ul>
418 * <li>if {@link FileUtils#getFolderName(String)} return null, return false</li>
419 * <li>if target directory already exists, return true</li>
420 * <li>return {@link java.io.File#makeFolder}</li>
421 * </ul>
422 */
423 public static boolean makeDirs(String filePath) {
424 String folderName = getFolderName(filePath);
425 if (StringUtils.isEmpty(folderName)) {
426 return false;
427 }
428
429 File folder = new File(folderName);
430 return (folder.exists() && folder.isDirectory()) ? true : folder.mkdirs();
431 }
432
433 /**
434 * @param filePath
435 * @return
436 * @see #makeDirs(String)
437 */
438 public static boolean makeFolders(String filePath) {
439 return makeDirs(filePath);
440 }
441
442 /**
443 * Indicates if this file represents a file on the underlying file system.
444 *
445 * @param filePath
446 * @return
447 */
448 public static boolean isFileExist(String filePath) {
449 if (StringUtils.isBlank(filePath)) {
450 return false;
451 }
452
453 File file = new File(filePath);
454 return (file.exists() && file.isFile());
455 }
456
457 /**
458 * Indicates if this file represents a directory on the underlying file system.
459 *
460 * @param directoryPath
461 * @return
462 */
463 public static boolean isFolderExist(String directoryPath) {
464 if (StringUtils.isBlank(directoryPath)) {
465 return false;
466 }
467
468 File dire = new File(directoryPath);
469 return (dire.exists() && dire.isDirectory());
470 }
471
472 /**
473 * delete file or directory
474 * <ul>
475 * <li>if path is null or empty, return true</li>
476 * <li>if path not exist, return true</li>
477 * <li>if path exist, delete recursion. return true</li>
478 * <ul>
479 *
480 * @param path
481 * @return
482 */
483 public static boolean deleteFile(String path) {
484 if (StringUtils.isBlank(path)) {
485 return true;
486 }
487
488 File file = new File(path);
489 if (!file.exists()) {
490 return true;
491 }
492 if (file.isFile()) {
493 return file.delete();
494 }
495 if (!file.isDirectory()) {
496 return false;
497 }
498 for (File f : file.listFiles()) {
499 if (f.isFile()) {
500 f.delete();
501 } else if (f.isDirectory()) {
502 deleteFile(f.getAbsolutePath());
503 }
504 }
505 return file.delete();
506 }
507
508 /**
509 * get file size
510 * <ul>
511 * <li>if path is null or empty, return -1</li>
512 * <li>if path exist and it is a file, return file size, else return -1</li>
513 * <ul>
514 *
515 * @param path
516 * @return returns the length of this file in bytes. returns -1 if the file does not exist.
517 */
518 public static long getFileSize(String path) {
519 if (StringUtils.isBlank(path)) {
520 return -1;
521 }
522
523 File file = new File(path);
524 return (file.exists() && file.isFile() ? file.length() : -1);
525 }
526 }
十三、assets和raw资源工具类 ResourceUtils.java
1 public class ResourceUtils {
2
3 private ResourceUtils() {
4 throw new AssertionError();
5 }
6
7 /**
8 * get an asset using ACCESS_STREAMING mode. This provides access to files that have been bundled with an
9 * application as assets -- that is, files placed in to the "assets" directory.
10 *
11 * @param context
12 * @param fileName The name of the asset to open. This name can be hierarchical.
13 * @return
14 */
15 public static String geFileFromAssets(Context context, String fileName) {
16 if (context == null || StringUtils.isEmpty(fileName)) {
17 return null;
18 }
19
20 StringBuilder s = new StringBuilder("");
21 try {
22 InputStreamReader in = new InputStreamReader(context.getResources().getAssets().open(fileName));
23 BufferedReader br = new BufferedReader(in);
24 String line;
25 while ((line = br.readLine()) != null) {
26 s.append(line);
27 }
28 return s.toString();
29 } catch (IOException e) {
30 e.printStackTrace();
31 return null;
32 }
33 }
34
35 /**
36 * get content from a raw resource. This can only be used with resources whose value is the name of an asset files
37 * -- that is, it can be used to open drawable, sound, and raw resources; it will fail on string and color
38 * resources.
39 *
40 * @param context
41 * @param resId The resource identifier to open, as generated by the appt tool.
42 * @return
43 */
44 public static String geFileFromRaw(Context context, int resId) {
45 if (context == null) {
46 return null;
47 }
48
49 StringBuilder s = new StringBuilder();
50 try {
51 InputStreamReader in = new InputStreamReader(context.getResources().openRawResource(resId));
52 BufferedReader br = new BufferedReader(in);
53 String line;
54 while ((line = br.readLine()) != null) {
55 s.append(line);
56 }
57 return s.toString();
58 } catch (IOException e) {
59 e.printStackTrace();
60 return null;
61 }
62 }
63
64 /**
65 * same to {@link ResourceUtils#geFileFromAssets(Context, String)}, but return type is List<String>
66 *
67 * @param context
68 * @param fileName
69 * @return
70 */
71 public static List<String> geFileToListFromAssets(Context context, String fileName) {
72 if (context == null || StringUtils.isEmpty(fileName)) {
73 return null;
74 }
75
76 List<String> fileContent = new ArrayList<String>();
77 try {
78 InputStreamReader in = new InputStreamReader(context.getResources().getAssets().open(fileName));
79 BufferedReader br = new BufferedReader(in);
80 String line;
81 while ((line = br.readLine()) != null) {
82 fileContent.add(line);
83 }
84 br.close();
85 return fileContent;
86 } catch (IOException e) {
87 e.printStackTrace();
88 return null;
89 }
90 }
91
92 /**
93 * same to {@link ResourceUtils#geFileFromRaw(Context, int)}, but return type is List<String>
94 *
95 * @param context
96 * @param resId
97 * @return
98 */
99 public static List<String> geFileToListFromRaw(Context context, int resId) {
100 if (context == null) {
101 return null;
102 }
103
104 List<String> fileContent = new ArrayList<String>();
105 BufferedReader reader = null;
106 try {
107 InputStreamReader in = new InputStreamReader(context.getResources().openRawResource(resId));
108 reader = new BufferedReader(in);
109 String line = null;
110 while ((line = reader.readLine()) != null) {
111 fileContent.add(line);
112 }
113 reader.close();
114 return fileContent;
115 } catch (IOException e) {
116 e.printStackTrace();
117 return null;
118 }
119 }
120 }
十四、单例工具类 SingletonUtils.java
1 public abstract class SingletonUtils<T> {
2
3 private T instance;
4
5 protected abstract T newInstance();
6
7 public final T getInstance() {
8 if (instance == null) {
9 synchronized (SingletonUtils.class) {
10 if (instance == null) {
11 instance = newInstance();
12 }
13 }
14 }
15 return instance;
16 }
17 }
十五、数据库工具类 SqliteUtils.java
1 public class SqliteUtils {
2
3 private static volatile SqliteUtils instance;
4
5 private DbHelper dbHelper;
6 private SQLiteDatabase db;
7
8 private SqliteUtils(Context context) {
9 dbHelper = new DbHelper(context);
10 db = dbHelper.getWritableDatabase();
11 }
12
13 public static SqliteUtils getInstance(Context context) {
14 if (instance == null) {
15 synchronized (SqliteUtils.class) {
16 if (instance == null) {
17 instance = new SqliteUtils(context);
18 }
19 }
20 }
21 return instance;
22 }
23
24 public SQLiteDatabase getDb() {
25 return db;
26 }
27 }
时间： 2024-10-10 10:59:21