android快速開發--常用utils類

1、日志工具類L.java

package com.zhy.utils;  
  
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;// 是否需要打印bug，可以在application的onCreate函數里面初始化  
    private static final String TAG = "way";  
  
    // 下面四個是默認tag的函數  
    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的函數  
    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，注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志記錄到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  
{  
    /** 
     * 保存在手機里面的文件名 
     */  
    public static final String FILE_NAME = "share_data";  
  
    /** 
     * 保存數據的方法，我們需要拿到保存數據的具體類型，然后根據類型調用不同的保存方法 
     *  
     * @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);  
    }  
  
    /** 
     * 得到保存數據的方法，我們根據默認值得到保存的數據的具體類型，然后調用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);  
    }  
  
    /** 
     * 清除所有數據 
     * @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();  
    }  
  
    /** 
     * 創建一個解決SharedPreferencesCompat.apply方法的一個兼容類 
     *  
     * @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，對外公布出put，get，remove，clear等等方法；

 

注意一點，里面所有的commit操作使用了SharedPreferencesCompat.apply進行了替代，目的是盡可能的使用apply代替commit

首先說下為什么，因為commit方法是同步的，並且我們很多時候的commit操作都是UI線程中，畢竟是IO操作，盡可能異步；

所以我們使用apply進行替代，apply異步的進行寫入；

但是apply相當於commit來說是new API呢，為了更好的兼容，我們做了適配；

SharedPreferencesCompat也可以給大家創建兼容類提供了一定的參考~~

4、單位轉換類 DensityUtils

package com.kevin.densityutils;

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

/**
 * Created by ${火龍裸先生} on 2016/11/3.
 * 郵箱：[e-mail]
 */
public class DensityUtils {
    private DensityUtils() {
        /* cannot be instantiated */
        throw new UnsupportedOperationException("cannot be instantiated");
    }

    /**
     * dp轉px
     *
     * @param context
     * @param dpVal
     * @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 spVal
     * @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 context
     * @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卡的剩余容量 單位byte 
     *  
     * @return 
     */  
    public static long getSDCardAllSize()  
    {  
        if (isSDCardEnable())  
        {  
            StatFs stat = new StatFs(getSDCardPath());  
            // 獲取空閑的數據塊的數量  
            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余可用容量字節數，單位byte 
     *  
     * @param filePath 
     * @return 容量字節 SDCard可用空間，內部存儲可用空間 
     */  
    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  
        {// 如果是內部存儲的路徑，則獲取內存存儲的可用容量  
            filePath = Environment.getDataDirectory().getAbsolutePath();  
        }  
        StatFs stat = new StatFs(filePath);  
        long availableBlocks = (long) stat.getAvailableBlocks() - 4;  
        return stat.getBlockSize() * availableBlocks;  
    }  
  
    /** 
     * 獲取系統存儲路徑 
     *  
     * @return 
     */  
    public static String getRootDirectoryPath()  
    {  
        return Environment.getRootDirectory().getAbsolutePath();  
    }  
  
  
}  

6、屏幕相關輔助類 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;  
  
/** 
 * 獲得屏幕相關的輔助類 
 *  
 *  
 *  
 */  
public class ScreenUtils  
{  
    private ScreenUtils()  
    {  
        /* cannot be instantiated */  
        throw new UnsupportedOperationException("cannot be instantiated");  
    }  
  
    /** 
     * 獲得屏幕高度 
     *  
     * @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;  
    }  
  
    /** 
     * 獲得屏幕寬度 
     *  
     * @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;  
    }  
  
    /** 
     * 獲得狀態欄的高度 
     *  
     * @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;  
    }  
  
    /** 
     * 獲取當前屏幕截圖，包含狀態欄 
     *  
     * @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;  
  
    }  
  
    /** 
     * 獲取當前屏幕截圖，不包含狀態欄 
     *  
     * @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");  
  
    }  
  
    /** 
     * 獲取應用程序名稱 
     */  
    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;  
    }  
  
    /** 
     * [獲取應用程序版本名稱信息] 
     *  
     * @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;  
  
/** 
 * 打開或關閉軟鍵盤 
 *  
 * @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、網絡相關輔助類 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;  
  
/** 
 * 跟網絡相關的工具類 
 *  
 *  
 *  
 */  
public class NetUtils  
{  
    private NetUtils()  
    {  
        /* cannot be instantiated */  
        throw new UnsupportedOperationException("cannot be instantiated");  
    }  
  
    /** 
     * 判斷網絡是否連接 
     *  
     * @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;  
  
    }  
  
    /** 
     * 打開網絡設置界面 
     */  
    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, 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);  
    }  
  
  
    /** 
     * 異步的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();  
    }  
  
    /** 
     * 異步的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，獲得返回數據 
     *  
     * @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 發送POST方法的請求  
     *   
     * @param url  
     *            發送請求的 URL  
     * @param param  
     *            請求參數，請求參數應該是 name1=value1&name2=value2 的形式。  
     * @return 所代表遠程資源的響應結果  
     * @throws Exception  
     */  
    public static String doPost(String url, String param)   
    {  
        PrintWriter out = null;  
        BufferedReader in = null;  
        String result = "";  
        try  
        {  
            URL realUrl = new URL(url);  
            // 打開和URL之間的連接  
            HttpURLConnection conn = (HttpURLConnection) realUrl  
                    .openConnection();  
            // 設置通用的請求屬性  
            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);  
            // 發送POST請求必須設置如下兩行  
            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對象對應的輸出流  
                out = new PrintWriter(conn.getOutputStream());  
                // 發送請求參數  
                out.print(param);  
                // flush輸出流的緩沖  
                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;  
    }  
}