java - JSON 错误 org.json.JSONException : No value for item

Question

稍微调整 JSON 响应后，错误已更改为 W/System.err: org.json.JSONException: No value for retCode。

The complete error:

04-03 12:53:26.624 14366-14366/com.allianz.azemployee W/System.err: org.json.JSONException: No value for retCode
04-03 12:53:26.624 14366-14366/com.allianz.azemployee W/System.err:     at org.json.JSONObject.get(JSONObject.java:389)
04-03 12:53:26.624 14366-14366/com.allianz.azemployee W/System.err:     at org.json.JSONObject.getString(JSONObject.java:550)
04-03 12:53:26.624 14366-14366/com.allianz.azemployee W/System.err:     at com.allianz.azemployee.ActivityRegister$2.serviceResult(ActivityRegister.java:194)
04-03 12:53:26.624 14366-14366/com.allianz.azemployee W/System.err:     at com.allianz.azemployee.Net$1$1.run(Net.java:420)
04-03 12:53:26.624 14366-14366/com.allianz.azemployee W/System.err:     at android.os.Handler.handleCallback(Handler.java:739)
04-03 12:53:26.625 14366-14366/com.allianz.azemployee W/System.err:     at android.os.Handler.dispatchMessage(Handler.java:95)
04-03 12:53:26.625 14366-14366/com.allianz.azemployee W/System.err:     at android.os.Looper.loop(Looper.java:148)
04-03 12:53:26.625 14366-14366/com.allianz.azemployee W/System.err:     at android.app.ActivityThread.main(ActivityThread.java:5417)
04-03 12:53:26.625 14366-14366/com.allianz.azemployee W/System.err:     at java.lang.reflect.Method.invoke(Native Method)
04-03 12:53:26.625 14366-14366/com.allianz.azemployee W/System.err:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
04-03 12:53:26.625 14366-14366/com.allianz.azemployee W/System.err:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
04-03 12:53:26.703 14366-14454/com.allianz.azemployee V/RenderScript: 0x9d789000 Launching thread(s), CPUs 4

这是我的 ActivityRegister.java 类:

public class ActivityRegister extends AppCompatActivity implements View.OnClickListener {

    Button btnRequestPin, btnConfirm, btnRequestNewPin;
    EditText editTextEmail;
    EditText editTextPin;

    private static final String FIRST_START_KEY = "first_start";
    private static final boolean ALWAYS_SEND_FIRST_START_BROADCAST = false;

    private String emailTemp, tokenTemp;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_register);
        btnRequestPin = (Button)findViewById(R.id.btn_request_pin);
        btnConfirm = (Button)findViewById(R.id.btn_confirm);
        btnRequestNewPin = (Button)findViewById(R.id.btn_request_newpin);
        editTextEmail = (EditText) findViewById(R.id.editText_mail);
        editTextPin = (EditText) findViewById(R.id.editText_pin);

        btnRequestPin.setOnClickListener(this);
        btnConfirm.setOnClickListener(this);
        btnRequestNewPin.setOnClickListener(this);
    }

    @Override
    protected void onNewIntent(Intent intent) {
        super.onNewIntent(intent);
    }

    @Override
    public void onBackPressed() {
        super.onBackPressed();
        finish();
        Intent intent = new Intent(this,ActivityLogin.class);
        this.startActivity(intent);
    }

    @Override
    public void onClick(View v) {
        if(v == btnConfirm){

            final String email = editTextEmail.getText().toString();
            final String token = editTextPin.getText().toString();

            if (email == null || email.length() == 0){
                Toast.makeText(this,"Email required",Toast.LENGTH_SHORT).show();
                return;
            }

            if (token == null || token.length() == 0){
                Toast.makeText(this,"OTP required",Toast.LENGTH_SHORT).show();
                return;
            }

            //Check if email is valid
            if(!android.util.Patterns.EMAIL_ADDRESS.matcher(email).matches()){
                Toast.makeText(this,"Valid email required.",Toast.LENGTH_SHORT).show();
                return;
            }

            String postBody = Net.getInstance().getJSONForRegister(email,token);
            Net.getInstance().callServiceWithURLPart(this, Net.kURLPartEmpAuthentication, postBody, new Net.ICallServiceResult() {
                @Override
                public void serviceResult(String urlPart, boolean expected, String errorMsg) {

                    if(!expected){

                        if(errorMsg!=null){
                            Net.fastToast(ActivityRegister.this,"Unable to register. Try again.\n\n"+errorMsg);
                        }
                        else {
                            Net.fastToast(ActivityRegister.this,"Unable to register. Try again.");
                        }
                    }
                    else {
                        try {
                            JSONObject jsonObject = new JSONObject(errorMsg);

                            String retCode = jsonObject.getString("retCode");
                            String status = jsonObject.getString("status");

                            int retCodeInt = Integer.parseInt(retCode);
                            Net.fastToast(ActivityRegister.this,status);

                            if (retCodeInt==0) { //Registration success

                                //Store user-email and token
                                Net.getInstance().saveUserWithValues(ActivityRegister.this, email, token, "");
                                //Take user to login screen.
                                ActivityRegister.this.finish();
                            }
                        } catch (JSONException e) {
                            e.printStackTrace();
                            Net.fastToast(ActivityRegister.this,"Unable to get valid response for registration. Try again.");
                        }
                    }
                }
            });
        }
        if(v == btnRequestPin || v == btnRequestNewPin){

            final String email = editTextEmail.getText().toString();

            if (email == null || email.length() == 0){
                Toast.makeText(this,"Email required",Toast.LENGTH_SHORT).show();
                return;
            }

            //Check if email is valid
            if(!android.util.Patterns.EMAIL_ADDRESS.matcher(email).matches()){
                Toast.makeText(this,"Valid email required.",Toast.LENGTH_SHORT).show();
                return;
            }

            final Button button = (Button) v;
            String postBody = Net.getInstance().getJSONForPinGeneration(email);
            Net.getInstance().callServiceWithURLPart(this, Net.kURLPartEmpAuthentication, postBody, new Net.ICallServiceResult() {
                @Override
                public void serviceResult(String urlPart, boolean expected, String errorMsg) {

                    if(!expected){
                        Log.i("Aditi","errorMsg== " +errorMsg);
                        if(errorMsg!=null){
                            Net.fastToast(ActivityRegister.this,"Unable to generate pin. Try again.\n\n"+errorMsg);
                        }
                        else {
                            Net.fastToast(ActivityRegister.this,"Unable to generate pin. Try again.");
                        }
                    }
                    else {
                        try {
                            JSONObject jsonObject = new JSONObject(errorMsg);

                            String retCode = jsonObject.getString("retCode");
                            String status = jsonObject.getString("status");

                            Log.i("Aditi","retCode===" + retCode + " ,status== "+status);
                            Log.i("Aditi","errorMsg== " +errorMsg);

                            int retCodeInt = Integer.parseInt(retCode);
                            Net.fastToast(ActivityRegister.this,status);

                            if(retCodeInt == 0 && button == btnRequestNewPin){

                                ActivityRegister.this.finish(); //take user to login on success.
                            }

                        } catch (JSONException e) {
                            e.printStackTrace();
                            Net.fastToast(ActivityRegister.this,"Unable to get valid response for pin generation. Try again.");
                        }
                    }

                }
            });
        }
    }
}

这是我给出的 stringResponse:

public void callServiceWithURLPart(final Activity activity, final String urlPart, final String postBody, final ICallServiceResult callServiceResult){

        final ProgressDialog progress = new ProgressDialog(activity);
        progress.setTitle("Processing..");
        progress.setProgressStyle(android.R.attr.progressBarStyleSmall);
        //progress.setMessage("Connecting...");
        progress.show();

        ConnectivityManager connMgr = (ConnectivityManager)
                activity.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
        if (networkInfo != null && networkInfo.isConnected()) {


            Runnable r = new Runnable() {
                @Override
                public void run() {

                    OkHttpClient client = new OkHttpClient.Builder().connectTimeout(60, TimeUnit.SECONDS).build();

                    try{

                        String servicePath = kURLBase + urlPart;

                        Log.d("OkHttpClient","servicePath = "+servicePath);
                        Log.d("postBody",postBody);

                        Request request = new Request.Builder()
                                .url(servicePath)
                                .put(RequestBody.create(MEDIA_TYPE_JSON, postBody))
                                .build();

                        final Response response = client.newCall(request).execute();
                        if (!response.isSuccessful()) throw new IOException("Unexpected code " + response);

                        //final String stringResponse = response.body().string();

                        final String stringResponse = "{'serviceName': 'registerToken', 'emailID': '', 'token': ''}";

                        if(stringResponse!=null){
                            Log.d("ServiceResponseString",stringResponse);
                        }else {
                            Log.d("ServiceResponseString","null");
                        }

                        if(callServiceResult!=null){
                            activity.runOnUiThread(new Runnable() {
                                @Override
                                public void run() {
                                    progress.dismiss();
                                    if(stringResponse!=null){
                                        callServiceResult.serviceResult(urlPart,true,stringResponse);
                                    }
                                    else {
                                        callServiceResult.serviceResult(urlPart,false,stringResponse);
                                    }
                                }
                            });
                        }
                    } catch (Exception e){

                        Log.d("OkHttpClient exception",e.toString());
                        final Exception _e = e;
                        if(callServiceResult!=null){
                            activity.runOnUiThread(new Runnable() {
                                @Override
                                public void run() {
                                    progress.dismiss();
           callServiceResult.serviceResult(urlPart,false,_e.toString());
                                }
                            });
                        }
                    }
                }
            };
            Thread t = new Thread(r);
            t.start();
        } else {
            progress.dismiss();
            fastToast(activity,"Connect to internet and try again.");
        }
    }

我的基本 URL 是:public static final String kURLBase = "https://api-test.allianz.com/digithonempwebservice/rest";，当询问 stringResponse 时会提供该 URL。任何帮助将不胜感激。

Answer 1

试试这个:

String retCode = jsonObject.optString("retCode");

The difference is that optString returns the empty string ("") if the key you specify doesn't exist. getString on the other hand throws a JSONException. Use getString if it's an error for the data to be missing, or optString if you're not sure if it will be there.