android 4.0 socket问题

 StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder().detectDiskReads().detectDiskWrites().detectNetwork().penaltyLog().build());  
        StrictMode.setVmPolicy(new StrictMode.VmPolicy.Builder().detectLeakedSqlLiteObjects().penaltyLog().penaltyDeath().build());  


为什么 setThreadPolicy Builder().detectDiskReads()等等都出错  
     --------------------编程问答-------------------- 1.使用多线程
2. if (android.os.Build.VERSION.SDK_INT > 9) {
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder()
.permitAll().build();
StrictMode.setThreadPolicy(policy);
}

补充：移动开发 ,  Android