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android中异步任务的垃圾收集器过多

android performance logging memory-management

android中异步任务的垃圾收集器过多,android,performance,logging,memory-management,Android,Performance,Logging,Memory Management,我试图使用URL下载json对象，为此我创建了一个AsyncTask。每当我启动应用程序时，都会启动过多的垃圾收集器。我不能理解我哪里出错了。我没有执行任何高内存使用任务，只是试图调用api来响应json main活动代码： public class MainActivity extends AppCompatActivity { public class DownloadTask extends AsyncTask<String,Void,String>{ @Over

我试图使用URL下载json对象，为此我创建了一个AsyncTask。每当我启动应用程序时，都会启动过多的垃圾收集器。我不能理解我哪里出错了。我没有执行任何高内存使用任务，只是试图调用api来响应json

main活动代码：

public class MainActivity extends AppCompatActivity {


public class DownloadTask extends AsyncTask<String,Void,String>{

    @Override
    protected String doInBackground(String... urls) {

        String result=null;
        URL url;
        HttpURLConnection httpURLConnection=null;

        try {
            url= new URL(urls[0]);
            httpURLConnection= (HttpURLConnection) url.openConnection();
            InputStream inputStream= httpURLConnection.getInputStream();
            InputStreamReader inputStreamReader= new InputStreamReader(inputStream);
            int data= inputStreamReader.read();
            while(data !=1){
                char current= (char) data;
                result +=current;
                data= inputStreamReader.read();
            }
            return result;

        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }

    @Override
    protected void onPostExecute(String result) {
        super.onPostExecute(result);
        Log.i("webssite Content :",result);
    }
}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    DownloadTask downloadTask= new DownloadTask();
    downloadTask.execute("http://api.openweathermap.org/data/2.5/weather?q=London&appid=5868b18238384fb4bdb3123jn9f0847cc");
}}

public类MainActivity扩展了AppCompatActivity{
公共类DownloadTask扩展了AsyncTask{
@凌驾
受保护的字符串doInBackground（字符串…URL）{
字符串结果=null；
网址；
HttpURLConnection HttpURLConnection=null；
试一试{
url=新url（url[0]）；
httpURLConnection=（httpURLConnection）url.openConnection（）；
InputStream InputStream=httpURLConnection.getInputStream（）；
InputStreamReader InputStreamReader=新的InputStreamReader（inputStream）；
int data=inputStreamReader.read（）；
while（数据！=1）{
当前字符=（字符）数据；
结果+=电流；
data=inputStreamReader.read（）；
}
返回结果；
}捕获（格式错误）{
e、 printStackTrace（）；
}捕获（IOE异常）{
e、 printStackTrace（）；
}
返回null；
}
@凌驾
受保护的void onPostExecute（字符串结果）{
super.onPostExecute（结果）；
Log.i（“网站内容：”，结果）；
}
}
@凌驾
创建时受保护的void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
setContentView（R.layout.activity_main）；
DownloadTask DownloadTask=新的DownloadTask（）；
下载任务。执行（“http://api.openweathermap.org/data/2.5/weather?q=London&appid=5868b18238384fb4bdb3123jn9f0847cc");
}}
Logcat

06-19 08:45:57.149 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed <1K, 28% free 4438K/6144K, paused 3ms, total 3ms
06-19 08:45:57.149 6269-6283/com.hemkar.jsondemo I/dalvikvm-heap: Grow heap (frag case) to 5.091MB for 720030-byte allocation
06-19 08:45:57.149 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 468K, 24% free 4672K/6144K, paused 6ms, total 6ms
06-19 08:45:57.159 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 1172K, 36% free 3969K/6144K, paused 5ms, total 5ms
06-19 08:45:57.159 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed <1K, 28% free 4438K/6144K, paused 3ms, total 3ms
06-19 08:45:57.159 6269-6283/com.hemkar.jsondemo I/dalvikvm-heap: Grow heap (frag case) to 5.091MB for 720034-byte allocation
06-19 08:45:57.159 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 468K, 24% free 4672K/6144K, paused 3ms, total 3ms
06-19 08:45:57.169 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 1172K, 36% free 3969K/6144K, paused 3ms, total 3ms
06-19 08:45:57.169 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed <1K, 28% free 4438K/6144K, paused 2ms, total 2ms
06-19 08:45:57.169 6269-6283/com.hemkar.jsondemo I/dalvikvm-heap: Grow heap (frag case) to 5.091MB for 720036-byte allocation
06-19 08:45:57.179 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 468K, 24% free 4672K/6144K, paused 4ms, total 4ms
06-19 08:45:57.179 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 1172K, 36% free 3969K/6144K, paused 3ms, total 3ms
06-19 08:45:57.189 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed <1K, 28% free 4438K/6144K, paused 7ms, total 7ms
06-19 08:45:57.189 6269-6283/com.hemkar.jsondemo I/dalvikvm-heap: Grow heap (frag case) to 5.091MB for 720040-byte allocation
06-19 08:45:57.189 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 468K, 24% free 4672K/6144K, paused 3ms, total 3ms
06-19 08:45:57.199 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 1172K, 36% free 3969K/6144K, paused 2ms, total 2ms
06-19 08:45:57.199 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed <1K, 28% free 4438K/6144K, paused 3ms, total 3ms
06-19 08:45:57.199 6269-6283/com.hemkar.jsondemo I/dalvikvm-heap: Grow heap (frag case) to 5.091MB for 720042-byte allocation
06-19 08:45:57.199 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 468K, 24% free 4672K/6144K, paused 3ms, total 3ms
06-19 08:45:57.209 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 1172K, 36% free 3969K/6144K, paused 3ms, total 3ms
06-19 08:45:57.219 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed <1K, 28% free 4438K/6144K, paused 5ms, total 5ms
06-19 08:45:57.219 6269-6283/com.hemkar.jsondemo I/dalvikvm-heap: Grow heap (frag case) to 5.091MB for 720046-byte allocation
06-19 08:45:57.229 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 468K, 24% free 4672K/6144K, paused 4ms, total 4ms
06-19 08:45:57.229 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 1172K, 36% free 3969K/6144K, paused 2ms, total 2ms
06-19 08:45:57.239 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed <1K, 28% free 4438K/6144K, paused 5ms, total 5ms
06-19 08:45:57.239 6269-6283/com.hemkar.jsondemo I/dalvikvm-heap: Grow heap (frag case) to 5.091MB for 720048-byte allocation
06-19 08:45:57.239 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 468K, 24% free 4672K/6144K, paused 4ms, total 4ms
06-19 08:45:57.249 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 1172K, 36% free 3969K/6144K, paused 4ms, total 4ms
06-19 08:45:57.249 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed <1K, 28% free 4438K/6144K, paused 5ms, total 5ms
06-19 08:45:57.249 6269-6283/com.hemkar.jsondemo I/dalvikvm-heap: Grow heap (frag case) to 5.091MB for 720052-byte allocation
06-19 08:45:57.259 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 468K, 24% free 4672K/6144K, paused 5ms, total 5ms
06-19 08:45:57.259 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed 1172K, 36% free 3969K/6144K, paused 3ms, total 3ms
06-19 08:45:57.269 6269-6283/com.hemkar.jsondemo D/dalvikvm: GC_FOR_ALLOC freed <1K, 28% free 4438K/6144K, paused 8ms, total 8ms
06-19 0

06-19 08:45:57.149 6269-6283/com.hemkar.jsondemo D/dalvikvm:GC_FOR_ALLOC freed我认为，因为在你的代码while（data！=1）中，correct应该是while（data！=-1）。循环是无限的
您是使用真实设备还是仅使用虚拟设备进行了尝试？我使用emulator进行了尝试，您的意思是它在真实设备中可以正常工作？我同意，如果到达流的末尾，则返回read（）返回-1。