1. 程式人生 > >Android 常用輔助工具類Utils總結

Android 常用輔助工具類Utils總結

Android 專案中常常會用一些輔助工具類,便於我們在開發中使用。下面做一下總結。

1、日誌工具類L.java

    import android.util.Log;   
    /** 
     * Log統一管理類 
     */  
    public class L  
    {  

        private L()  
        {  
            /* cannot be instantiated */  
            throw new UnsupportedOperationException("cannot be instantiated"
); } public static boolean isDebug = true;// 是否需要列印bug,可以在application的onCreate函式裡面初始化 private static final String TAG = "way"; // 下面四個是預設tag的函式 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); } // 下面是傳入自定義tag的函式 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); } }

網上看到的類,註釋上應該原創作者的名字,很簡單的一個類;網上也有很多提供把日誌記錄到SDCard上的,不過我是從來沒記錄過,所以引入個最簡單的,大家可以進行評價是否需要擴充~~

2、Toast統一管理類

    package com.zhy.utils;  

    import android.content.Context;  
    import android.widget.Toast;  

    /** 
     * Toast統一管理類 
     *  
     */  
    public class T  
    {  

        private T()  
        {  
            /* cannot be instantiated */  
            throw new UnsupportedOperationException("cannot be instantiated");  
        }  

        public static boolean isShow = true;  

        /** 
         * 短時間顯示Toast 
         *  
         * @param context 
         * @param message 
         */  
        public static void showShort(Context context, CharSequence message)  
        {  
            if (isShow)  
                Toast.makeText(context, message, Toast.LENGTH_SHORT).show();  
        }  

        /** 
         * 短時間顯示Toast 
         *  
         * @param context 
         * @param message 
         */  
        public static void showShort(Context context, int message)  
        {  
            if (isShow)  
                Toast.makeText(context, message, Toast.LENGTH_SHORT).show();  
        }  

        /** 
         * 長時間顯示Toast 
         *  
         * @param context 
         * @param message 
         */  
        public static void showLong(Context context, CharSequence message)  
        {  
            if (isShow)  
                Toast.makeText(context, message, Toast.LENGTH_LONG).show();  
        }  

        /** 
         * 長時間顯示Toast 
         *  
         * @param context 
         * @param message 
         */  
        public static void showLong(Context context, int message)  
        {  
            if (isShow)  
                Toast.makeText(context, message, Toast.LENGTH_LONG).show();  
        }  

        /** 
         * 自定義顯示Toast時間 
         *  
         * @param context 
         * @param message 
         * @param duration 
         */  
        public static void show(Context context, CharSequence message, int duration)  
        {  
            if (isShow)  
                Toast.makeText(context, message, duration).show();  
        }  

        /** 
         * 自定義顯示Toast時間 
         *  
         * @param context 
         * @param message 
         * @param duration 
         */  
        public static void show(Context context, int message, int duration)  
        {  
            if (isShow)  
                Toast.makeText(context, message, duration).show();  
        }  

    }  

也是非常簡單的一個封裝,能省則省了~~

3、SharedPreferences封裝類SPUtils

    package com.zhy.utils;  

    import java.lang.reflect.InvocationTargetException;  
    import java.lang.reflect.Method;  
    import java.util.Map;  

    import android.content.Context;  
    import android.content.SharedPreferences;  

    public class SPUtils  
    {  
        /** 
         * 儲存在手機裡面的檔名 
         */  
        public static final String FILE_NAME = "share_data";  

        /** 
         * 儲存資料的方法,我們需要拿到儲存資料的具體型別,然後根據型別呼叫不同的儲存方法 
         *  
         * @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);  
        }  

        /** 
         * 得到儲存資料的方法,我們根據預設值得到儲存的資料的具體型別,然後呼叫相對於的方法獲取值 
         *  
         * @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;  
        }  

        /** 
         * 移除某個key值已經對應的值 
         * @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);  
        }  

        /** 
         * 清除所有資料 
         * @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);  
        }  

        /** 
         * 查詢某個key是否已經存在 
         * @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);  
        }  

        /** 
         * 返回所有的鍵值對 
         *  
         * @param context 
         * @return 
         */  
        public static Map<String, ?> getAll(Context context)  
        {  
            SharedPreferences sp = context.getSharedPreferences(FILE_NAME,  
                    Context.MODE_PRIVATE);  
            return sp.getAll();  
        }  

        /** 
         * 建立一個解決SharedPreferencesCompat.apply方法的一個相容類 
         *  
         * @author zhy 
         *  
         */  
        private static class SharedPreferencesCompat  
        {  
            private static final Method sApplyMethod = findApplyMethod();  

            /** 
             * 反射查詢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;  
            }  

            /** 
             * 如果找到則使用apply執行,否則使用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();  
            }  
        }  

    }  

對SharedPreference的使用做了建議的封裝,對外公佈出put,get,remove,clear等等方法;注意一點,裡面所有的commit操作使用了SharedPreferencesCompat.apply進行了替代,目的是儘可能的使用apply代替commit首先說下為什麼,因為commit方法是同步的,並且我們很多時候的commit操作都是UI執行緒中,畢竟是IO操作,儘可能非同步;所以我們使用apply進行替代,apply非同步的進行寫入;
但是apply相當於commit來說是new API呢,為了更好的相容,我們做了適配;
SharedPreferencesCompat也可以給大家建立相容類提供了一定的參考~~

4、單位轉換類 DensityUtils

    package com.zhy.utils;  

    import android.content.Context;  
    import android.util.TypedValue;  

    /** 
     * 常用單位轉換的輔助類 
     *  
     *  
     *  
     */  
    public class DensityUtils  
    {  
        private DensityUtils()  
        {  
            /* cannot be instantiated */  
            throw new UnsupportedOperationException("cannot be instantiated");  
        }  

        /** 
         * dp轉px 
         *  
         * @param context 
         * @param val 
         * @return 
         */  
        public static int dp2px(Context context, float dpVal)  
        {  
            return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,  
                    dpVal, context.getResources().getDisplayMetrics());  
        }  

        /** 
         * sp轉px 
         *  
         * @param context 
         * @param val 
         * @return 
         */  
        public static int sp2px(Context context, float spVal)  
        {  
            return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP,  
                    spVal, context.getResources().getDisplayMetrics());  
        }  

        /** 
         * px轉dp 
         *  
         * @param context 
         * @param pxVal 
         * @return 
         */  
        public static float px2dp(Context context, float pxVal)  
        {  
            final float scale = context.getResources().getDisplayMetrics().density;  
            return (pxVal / scale);  
        }  

        /** 
         * px轉sp 
         *  
         * @param fontScale 
         * @param pxVal 
         * @return 
         */  
        public static float px2sp(Context context, float pxVal)  
        {  
            return (pxVal / context.getResources().getDisplayMetrics().scaledDensity);  
        }  

    }  

5、SD卡相關輔助類 SDCardUtils

    package com.zhy.utils;  

    import java.io.File;  

    import android.os.Environment;  
    import android.os.StatFs;  

    /** 
     * SD卡相關的輔助類 
     *  
     *  
     *  
     */  
    public class SDCardUtils  
    {  
        private SDCardUtils()  
        {  
            /* cannot be instantiated */  
            throw new UnsupportedOperationException("cannot be instantiated");  
        }  

        /** 
         * 判斷SDCard是否可用 
         *  
         * @return 
         */  
        public static boolean isSDCardEnable()  
        {  
            return Environment.getExternalStorageState().equals(  
                    Environment.MEDIA_MOUNTED);  

        }  

        /** 
         * 獲取SD卡路徑 
         *  
         * @return 
         */  
        public static String getSDCardPath()  
        {  
            return Environment.getExternalStorageDirectory().getAbsolutePath()  
                    + File.separator;  
        }  

        /** 
         * 獲取SD卡的剩餘容量 單位byte 
         *  
         * @return 
         */  
        public static long getSDCardAllSize()  
        {  
            if (isSDCardEnable())  
            {  
                StatFs stat = new StatFs(getSDCardPath());  
                // 獲取空閒的資料塊的數量  
                long availableBlocks = (long) stat.getAvailableBlocks() - 4;  
                // 獲取單個數據塊的大小(byte)  
                long freeBlocks = stat.getAvailableBlocks();  
                return freeBlocks * availableBlocks;  
            }  
            return 0;  
        }  

        /** 
         * 獲取指定路徑所在空間的剩餘可用容量位元組數,單位byte 
         *  
         * @param filePath 
         * @return 容量位元組 SDCard可用空間,內部儲存可用空間 
         */  
        public static long getFreeBytes(String filePath)  
        {  
            // 如果是sd卡的下的路徑,則獲取sd卡可用容量  
            if (filePath.startsWith(getSDCardPath()))  
            {  
                filePath = getSDCardPath();  
            } else  
            {// 如果是內部儲存的路徑,則獲取記憶體儲存的可用容量  
                filePath = Environment.getDataDirectory().getAbsolutePath();  
            }  
            StatFs stat = new StatFs(filePath);  
            long availableBlocks = (long) stat.getAvailableBlocks() - 4;  
            return stat.getBlockSize() * availableBlocks;  
        }  

        /** 
         * 獲取系統儲存路徑 
         *  
         * @return 
         */  
        public static String getRootDirectoryPath()  
        {  
            return Environment.getRootDirectory().getAbsolutePath();  
        }  


    }  

6、螢幕相關輔助類 ScreenUtils

    package com.zhy.utils;  

    import android.app.Activity;  
    import android.content.Context;  
    import android.graphics.Bitmap;  
    import android.graphics.Rect;  
    import android.util.DisplayMetrics;  
    import android.view.View;  
    import android.view.WindowManager;  

    /** 
     * 獲得螢幕相關的輔助類 
     *  
     *  
     *  
     */  
    public class ScreenUtils  
    {  
        private ScreenUtils()  
        {  
            /* cannot be instantiated */  
            throw new UnsupportedOperationException("cannot be instantiated");  
        }  

        /** 
         * 獲得螢幕高度 
         *  
         * @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;  
        }  

        /** 
         * 獲得螢幕寬度 
         *  
         * @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;  
        }  

        /** 
         * 獲得狀態列的高度 
         *  
         * @param context 
         * @return 
         */  
        public static int getStatusHeight(Context context)  
        {  

            int statusHeight = -1;  
            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;  
        }  

        /** 
         * 獲取當前螢幕截圖,包含狀態列 
         *  
         * @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, 0, 0, width, height);  
            view.destroyDrawingCache();  
            return bp;  

        }  

        /** 
         * 獲取當前螢幕截圖,不包含狀態列 
         *  
         * @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, 0, statusBarHeight, width, height  
                    - statusBarHeight);  
            view.destroyDrawingCache();  
            return bp;  

        }  

    }  

7、App相關輔助類

    package com.zhy.utils;  

    import android.content.Context;  
    import android.content.pm.PackageInfo;  
    import android.content.pm.PackageManager;  
    import android.content.pm.PackageManager.NameNotFoundException;  

    /** 
     * 跟App相關的輔助類 
     *  
     *  
     *  
     */  
    public class AppUtils  
    {  

        private AppUtils()  
        {  
            /* cannot be instantiated */  
            throw new UnsupportedOperationException("cannot be instantiated");  

        }  

        /** 
         * 獲取應用程式名稱 
         */  
        public static String getAppName(Context context)  
        {  
            try  
            {  
                PackageManager packageManager = context.getPackageManager();  
                PackageInfo packageInfo = packageManager.getPackageInfo(  
                        context.getPackageName(), 0);  
                int labelRes = packageInfo.applicationInfo.labelRes;  
                return context.getResources().getString(labelRes);  
            } catch (NameNotFoundException e)  
            {  
                e.printStackTrace();  
            }  
            return null;  
        }  

        /** 
         * [獲取應用程式版本名稱資訊] 
         *  
         * @param context 
         * @return 當前應用的版本名稱 
         */  
        public static String getVersionName(Context context)  
        {  
            try  
            {  
                PackageManager packageManager = context.getPackageManager();  
                PackageInfo packageInfo = packageManager.getPackageInfo(  
                        context.getPackageName(), 0);  
                return packageInfo.versionName;  

            } catch (NameNotFoundException e)  
            {  
                e.printStackTrace();  
            }  
            return null;  
        }  

    }  

8、軟鍵盤相關輔助類KeyBoardUtils

    package com.zhy.utils;  

    import android.content.Context;  
    import android.view.inputmethod.InputMethodManager;  
    import android.widget.EditText;  

    /** 
     * 開啟或關閉軟鍵盤 
     *  
     * @author zhy 
     *  
     */  
    public class KeyBoardUtils  
    {  
        /** 
         * 打卡軟鍵盤 
         *  
         * @param mEditText 
         *            輸入框 
         * @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);  
        }  

        /** 
         * 關閉軟鍵盤 
         *  
         * @param mEditText 
         *            輸入框 
         * @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(), 0);  
        }  
    }  

9、網路相關輔助類 NetUtils

    package com.zhy.utils;  

    import android.app.Activity;  
    import android.content.ComponentName;  
    import android.content.Context;  
    import android.content.Intent;  
    import android.net.ConnectivityManager;  
    import android.net.NetworkInfo;  

    /** 
     * 跟網路相關的工具類 
     *  
     *  
     *  
     */  
    public class NetUtils  
    {  
        private NetUtils()  
        {  
            /* cannot be instantiated */  
            throw new UnsupportedOperationException("cannot be instantiated");  
        }  

        /** 
         * 判斷網路是否連線 
         *  
         * @param context 
         * @return 
         */  
        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;  
        }  

        /** 
         * 判斷是否是wifi連線 
         */  
        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;  

        }  

        /** 
         * 開啟網路設定介面 
         */  
        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, 0);  
        }  

    }  

10、Http相關輔助類 HttpUtils

    package com.zhy.utils;  

    import java.io.BufferedReader;  
    import java.io.ByteArrayOutputStream;  
    import java.io.IOException;  
    import java.io.InputStream;  
    import java.io.InputStreamReader;  
    import java.io.PrintWriter;  
    import java.net.HttpURLConnection;  
    import java.net.URL;  

    /** 
     * Http請求的工具類 
     *  
     * @author zhy 
     *  
     */  
    public class HttpUtils  
    {  

        private static final int TIMEOUT_IN_MILLIONS = 5000;  

        public interface CallBack  
        {  
            void onRequestComplete(String result);  
        }  


        /** 
         * 非同步的Get請求 
         *  
         * @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();  
        }  

        /** 
         * 非同步的Post請求 
         * @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請求,獲得返回資料 
         *  
         * @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() == 200)  
                {  
                    is = conn.getInputStream();  
                    baos = new ByteArrayOutputStream();  
                    int len = -1;  
                    byte[] buf = new byte[128];  

                    while ((len = is.read(buf)) != -1)  
                    {  
                        baos.write(buf, 0, len);  
                    }  
                    baos.flush();  
                    return baos.toString();  
                } else  
                {  
                    throw new RuntimeException(" responseCode is not 200 ... ");  
                }  

            } 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 傳送POST方法的請求  
         *   
         * @param url  
         *            傳送請求的 URL  
         * @param param  
         *            請求引數,請求引數應該是 name1=value1&name2=value2 的形式。  
         * @return 所代表遠端資源的響應結果  
         * @throws Exception  
         */  
        public static String doPost(String url, String param)   
        {  
            PrintWriter out = null;  
            BufferedReader in = null;  
            String result = "";  
            try  
            {  
                URL realUrl = new URL(url);  
                // 開啟和URL之間的連線  
                HttpURLConnection conn = (HttpURLConnection) realUrl  
                        .openConnection();  
                // 設定通用的請求屬性  
                conn.setRequestProperty("accept", "*/*");  
                conn.setRequestProperty("connection", "Keep-Alive");  
                conn.setRequestMethod("POST");  
                conn.setRequestProperty("Content-Type",  
                        "application/x-www-form-urlencoded");  
                conn.setRequestProperty("charset", "utf-8");  
                conn.setUseCaches(false);  
                // 傳送POST請求必須設定如下兩行  
                conn.setDoOutput(true);  
                conn.setDoInput(true);  
                conn.setReadTimeout(TIMEOUT_IN_MILLIONS);  
                conn.setConnectTimeout(TIMEOUT_IN_MILLIONS);  

                if (param != null && !param.trim().equals(""))  
                {  
                    // 獲取URLConnection物件對應的輸出流  
                    out = new PrintWriter(conn.getOutputStream());  
                    // 傳送請求引數  
                    out.print(param);  
                    // flush輸出流的緩衝  
                    out.flush();  
                }  
                // 定義BufferedReader輸入流來讀取URL的響應  
                in = new BufferedReader(  
                        new InputStreamReader(conn.getInputStream()));  
                String line;  
                while ((line = in.readLine()) != null)  
                {  
                    result += line;  
                }  
            } catch (Exception e)  
            {  
                e.printStackTrace();  
            }  
            // 使用finally塊來關閉輸出流、輸入流  
            finally  
            {  
                try  
                {  
                    if (out != null)  
                    {  
                        out.close();  
                    }  
                    if (in != null)  
                    {  
                        in.close();  
                    }  
                } catch (IOException ex)  
                {  
                    ex.printStackTrace();  
                }  
            }  
            return result;  
        }  
    }