Gson输出com.google.Gson.JsonSyntaxException:java.io.EOFException：第1行第501列输入结束_Java_Android_Json

Gson输出com.google.Gson.JsonSyntaxException:java.io.EOFException：第1行第501列输入结束

java android json

Gson输出com.google.Gson.JsonSyntaxException:java.io.EOFException：第1行第501列输入结束,java,android,json,Java,Android,Json,我一直在使用Gson解析API中的JSON，以便在我的应用程序中使用。这是JSON输出的一个示例： {"getdashboarddata":{"version":"1.0.0","runtime":492.3939704895,"data":{"raw":{"personal":{"hashrate":0},"pool":{"hashrate":1705841},"network":{"hashrate":41430764.301,"esttimeperblock":94.46446656534

我一直在使用Gson解析API中的JSON，以便在我的应用程序中使用。这是JSON输出的一个示例：

{"getdashboarddata":{"version":"1.0.0","runtime":492.3939704895,"data":{"raw":{"personal":{"hashrate":0},"pool":{"hashrate":1705841},"network":{"hashrate":41430764.301,"esttimeperblock":94.464466565347,"nextdifficulty":578.78109116,"blocksuntildiffchange":1}},"personal":{"hashrate":0,"sharerate":"0.0000","sharedifficulty":0,"shares":{"valid":0,"invalid":0,"invalid_percent":0,"unpaid":0},"estimates":{"block":0,"fee":0,"donation":0,"payout":0}},"pool":{"info":{"name":"RAPIDHASH","currency":"DOGE"},"workers":2199,"hashrate":1.705841,"shares":{"valid":1866290,"invalid":15564,"invalid_percent":0.83,"estimated":1866214,"progress":100},"price":"0.00000073","difficulty":32,"target_bits":21},"system":{"load":[0.1,0.25,0.29]},"network":{"hashrate":41.430764301,"difficulty":911.23745057,"block":235378,"esttimeperblock":94.46,"nextdifficulty":578.78109116,"blocksuntildiffchange":1}}}}

这是logcat：

05-25 17:12:00.230  24143-24159/io.kd.figgycity50.mpos.mposchecker E/AndroidRuntime﹕ FATAL EXCEPTION: AsyncTask #1
Process: io.kd.figgycity50.mpos.mposchecker, PID: 24143
java.lang.RuntimeException: An error occured while executing doInBackground()
        at android.os.AsyncTask$3.done(AsyncTask.java:300)
        at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
        at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
        at java.util.concurrent.FutureTask.run(FutureTask.java:242)
        at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
        at java.lang.Thread.run(Thread.java:841)
 Caused by: com.google.gson.JsonSyntaxException: java.io.EOFException: End of input at line 1 column 501
        at com.google.gson.Gson.fromJson(Gson.java:813)
        at com.google.gson.Gson.fromJson(Gson.java:768)
        at com.google.gson.Gson.fromJson(Gson.java:717)
        at com.google.gson.Gson.fromJson(Gson.java:689)
        at io.kd.figgycity50.mpos.mposchecker.MainActivity$DownloadWebpageTask.doInBackground(MainActivity.java:77)
        at io.kd.figgycity50.mpos.mposchecker.MainActivity$DownloadWebpageTask.doInBackground(MainActivity.java:64)
        at android.os.AsyncTask$2.call(AsyncTask.java:288)
        at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:841)
 Caused by: java.io.EOFException: End of input at line 1 column 501
        at com.google.gson.stream.JsonReader.nextNonWhitespace(JsonReader.java:1377)
        at com.google.gson.stream.JsonReader.doPeek(JsonReader.java:471)
        at com.google.gson.stream.JsonReader.skipValue(JsonReader.java:1209)
        at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:170)
        at com.google.gson.Gson.fromJson(Gson.java:803)
            at com.google.gson.Gson.fromJson(Gson.java:768)
            at com.google.gson.Gson.fromJson(Gson.java:717)
            at com.google.gson.Gson.fromJson(Gson.java:689)
            at io.kd.figgycity50.mpos.mposchecker.MainActivity$DownloadWebpageTask.doInBackground(MainActivity.java:77)
            at io.kd.figgycity50.mpos.mposchecker.MainActivity$DownloadWebpageTask.doInBackground(MainActivity.java:64)
            at android.os.AsyncTask$2.call(AsyncTask.java:288)
            at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:841)

这是获取和解析JSON的代码：

private class DownloadWebpageTask extends AsyncTask<String, Void, String> {
        @Override
        protected String doInBackground(String... urls) {

            // params comes from the execute() call: params[0] is the url.
            String resp = null;
            try {
                resp =  downloadUrl(urls[0]);
            } catch (IOException e) {
                resp = "{\"getdashboarddata\":{\"data\":{\"personal\":{\"hashrate\":0},\"pool\":{\"info\":{\"name\":\"SET POOL IN SETTINGS\",\"currency\":\"???\"},\"hashrate\":0,\"difficulty\":0},\"network\":{\"hashrate\":0,\"difficulty\":0}}}}";
            }
            Gson gson = new Gson();
            Log.d("INFO", resp);
            MPOSDashStruct data = gson.fromJson(resp, MPOSDashStruct.class);
            TextView t = (TextView)findViewById(R.id.poolName);
            TextView t2 = (TextView)findViewById(R.id.khashMe);
            TextView t3 = (TextView)findViewById(R.id.khashPool);
            TextView t4 = (TextView)findViewById(R.id.khashNet);
            t.setText(data.getName());
            t2.setText(data.getMyHash());
            t3.setText(data.getPoolHash());
            t4.setText(data.getNetHash());
            return "Hello World. If you see this, you probably hack. Get out.";
        }

        private String downloadUrl(String myurl) throws IOException {
            InputStream is = null;
            // Only display the first 500 characters of the retrieved
            // web page content.
            int len = 500;

            try {
                URL url = new URL(myurl);
                HttpURLConnection conn = (HttpURLConnection) url.openConnection();
                conn.setReadTimeout(10000 /* milliseconds */);
                conn.setConnectTimeout(15000 /* milliseconds */);
                conn.setRequestMethod("GET");
                conn.setDoInput(true);
                // Starts the query
                conn.connect();
                int response = conn.getResponseCode();
                is = conn.getInputStream();

                // Convert the InputStream into a string
                String contentAsString = readIt(is, len);
                return contentAsString;

                // Makes sure that the InputStream is closed after the app is
                // finished using it.
            } finally {
                if (is != null) {
                    is.close();
                }
            }
        }

        public String readIt(InputStream stream, int len) throws IOException, UnsupportedEncodingException {
            Reader reader = null;
            reader = new InputStreamReader(stream, "UTF-8");
            char[] buffer = new char[len];
            reader.read(buffer);
            return new String(buffer);
        }
    }
}

代码看起来不错，Android Studio没有错误

编辑2：内容字符串输出

05-25 17:30:12.976  29974-29988/io.kd.figgycity50.mpos.mposchecker D/INFO﹕ {"getdashboarddata":{"version":"1.0.0","runtime":632.7919960022,"data":{"raw":{"personal":{"hashrate":0},"pool":{"hashrate":1675289},"network":{"hashrate":38541151.201,"esttimeperblock":61.161346587453,"nextdifficulty":538.41366248,"blocksuntildiffchange":1}},"personal":{"hashrate":0,"sharerate":"0.0000","sharedifficulty":0,"shares":{"valid":0,"invalid":0,"invalid_percent":0,"unpaid":0},"estimates":{"block":0,"fee":0,"donation":0,"payout":0}},"pool":{"info":{"name":"RAPIDHASH","currency":"DOGE"}

使用Log.d（“INFO”，contentAsString）

编辑：使用getContentLength后，新的logcat是：

05-25 17:50:19.203    5143-5157/io.kd.figgycity50.mpos.mposchecker W/dalvikvm﹕ threadid=11: thread exiting with uncaught exception (group=0x41bd4ba8)
05-25 17:50:19.203    5143-5157/io.kd.figgycity50.mpos.mposchecker E/AndroidRuntime﹕ FATAL EXCEPTION: AsyncTask #1
    Process: io.kd.figgycity50.mpos.mposchecker, PID: 5143
    java.lang.RuntimeException: An error occured while executing doInBackground()
            at android.os.AsyncTask$3.done(AsyncTask.java:300)
            at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
            at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
            at java.util.concurrent.FutureTask.run(FutureTask.java:242)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:841)
     Caused by: java.lang.NegativeArraySizeException: -1
            at io.kd.figgycity50.mpos.mposchecker.MainActivity$DownloadWebpageTask.readIt(MainActivity.java:120)
            at io.kd.figgycity50.mpos.mposchecker.MainActivity$DownloadWebpageTask.downloadUrl(MainActivity.java:104)
            at io.kd.figgycity50.mpos.mposchecker.MainActivity$DownloadWebpageTask.doInBackground(MainActivity.java:71)
            at io.kd.figgycity50.mpos.mposchecker.MainActivity$DownloadWebpageTask.doInBackground(MainActivity.java:64)
            at android.os.AsyncTask$2.call(AsyncTask.java:288)
            at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:841)

它指向我的代码的这一行：

public String readIt(InputStream stream, int len) throws IOException, UnsupportedEncodingException {
            Reader reader = null;
            reader = new InputStreamReader(stream, "UTF-8");
            char[] buffer = new char[len]; //this line, others added so you can understand
            reader.read(buffer);
            return new String(buffer);
        }

编辑3：指导Gson处理读取器效果很好，但新的错误再次出现。日志：

05-26 09:17:52.459  11810-11810/io.kd.figgycity50.mpos.mposchecker E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: io.kd.figgycity50.mpos.mposchecker, PID: 11810
    java.lang.RuntimeException: Unable to start activity ComponentInfo{io.kd.figgycity50.mpos.mposchecker/io.kd.figgycity50.mpos.mposchecker.MainActivity}: java.lang.NullPointerException
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
            at android.app.ActivityThread.access$800(ActivityThread.java:135)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:136)
            at android.app.ActivityThread.main(ActivityThread.java:5017)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
            at dalvik.system.NativeStart.main(Native Method)
     Caused by: java.lang.NullPointerException
            at io.kd.figgycity50.mpos.mposchecker.MainActivity.onCreate(MainActivity.java:49)
            at android.app.Activity.performCreate(Activity.java:5231)
            at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
            at android.app.ActivityThread.access$800(ActivityThread.java:135)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:136)
            at android.app.ActivityThread.main(ActivityThread.java:5017)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
            at dalvik.system.NativeStart.main(Native Method)

其中指出：

protected void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        SharedPreferences sharedPref = PreferenceManager.getDefaultSharedPreferences(this);
        String prefPool = sharedPref.getString("pref_pool", "https://doge.rapidhash.net/");
        String prefKey = sharedPref.getString("pref_key", "XXXX");
        new DownloadWebpageTask().execute(prefPool + "index.php?page=api&action=getdashboarddata&api_key=" + prefKey);
        TextView t = (TextView)findViewById(R.id.poolName); // this line
        TextView t2 = (TextView)findViewById(R.id.khashMe);
        TextView t3 = (TextView)findViewById(R.id.khashPool);
        TextView t4 = (TextView)findViewById(R.id.khashNet);
        t.setText(dashStruct.getName());
        t2.setText(dashStruct.getMyHash());
        t3.setText(dashStruct.getPoolHash());
        t4.setText(dashStruct.getNetHash());
    }

我不知道你为什么这么做

// Only display the first 500 characters of the retrieved
// web page content.
int len = 500;

如果您的JSON比这个长度长，那么您将其分解为JSON解析器无法解析的部分。读取完整的JSON字符串

从响应中获取信息

int len = conn.getContentLength();

从上面的

edit3

中，以下行似乎抛出了

NullPointerException

：

t.setText(dashStruct.getName());

我可以看出，您将

dashStruct

声明为类级变量，该变量将在AsyncTask

DownloadWebpageTask

中初始化

根据设计，AsyncTask将在主线程之外执行（确切地说，是AsyncTask#doInBackground（T）方法）。如果主线程执行

t.setText（dashStruct.getName（））时downloadWebPagetTask
尚未完成初始化dashStruct
-将抛出NPE-dashStruct
为空
若要通过此异常，请覆盖下载WebPagetTask
中的onPostExecute（）
，并将以下代码移到其中（将其从onCreate（Bundle）
中删除）：
我注意到，在您最初的帖子中，您正在从下载的WebPagetAsk#doInBackground（String…
更新您的UI（设置textview文本）。这将抛出一个IllegalStateException
，因为doInBackground（）
是在主线程之外处理的，主线程是唯一允许接触UI的线程<代码>onPostExecute（）

在主线程上处理。这就是你的UI逻辑应该去的地方。

你打印出

内容字符串了吗？您的响应是UTF8吗？我不知道响应是否是UTF8，因为它不是我的API。在文章中使用Log.d时，我编辑了contentAsString的输出，因为它太长，不适合评论。@user2758631啊，如果响应中不存在标题，该方法可能返回-1。这里的一个解决方案是将InputStream
直接传递给Gson
，而不是首先将其作为字符串读取。这样做之后，会出现一个新错误，但不会出现在下载的WebPagetTask中。请参阅编辑日志。
t.setText(dashStruct.getName());

@Override
protected void onPostExecute(String result) {

    if (dashStruct != null) {
        t.setText(dashStruct.getName());
        t2.setText(dashStruct.getMyHash());
        t3.setText(dashStruct.getPoolHash());
        t4.setText(dashStruct.getNetHash());
    } else {
        // Deal with dashStruct being null
    }
}