HttpURLConnection connect() method fails and crash

Question

I am trying to call a web service through the following code. But httpUrlConnection.connect() is failing and app begin to crash.

           try {
                URL serverAddress = new URL("http://thesaurus.altervista.org/thesaurus/v1?word=peace&language=en_US&key=code&output=json");

                HttpURLConnection connection = (HttpURLConnection) serverAddress.openConnection();
                connection.connect();

                int rc = connection.getResponseCode();
                if (rc == 200) {
                    String line = null;
                    BufferedReader br = new BufferedReader(new InputStreamReader(connection.getInputStream()));
                    StringBuilder sb = new StringBuilder();
                    while ((line = br.readLine()) != null)
                        sb.append(line + '\n');
                    JSONObject obj = (JSONObject) JSONValue.parse(sb.toString());
                    JSONArray array = (JSONArray)obj.get("response");
                    for (int i=0; i < array.size(); i++) {
                        JSONObject list = (JSONObject) ((JSONObject)array.get(i)).get("list");
                        System.out.println(list.get("category")+":"+list.get("synonyms"));
                    }
                } else System.out.println("HTTP error:"+rc);
                connection.disconnect();
            } catch (MalformedURLException e) {
                e.printStackTrace();
            } catch (ProtocolException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }

Logcat

    05-06 13:08:55.951 1133-1546/? D/NetworkController.MobileSignalController(4): onSignalStrengthsChanged signalStrength=SignalStrength: 11 35 -120 -160 -120 -1 -1 99 2147483647 2147483647 2147483647 2147483647 2147483647 gsm|lte 2147483647 -396 7 level=3
    updateTelephonySignalStrength: hasService=true ss=SignalStrength: 11 35 -120 -160 -120 -1 -1 99 2147483647 2147483647 2147483647 2147483647 2147483647 gsm|lte 2147483647 -396 7
05-06 13:08:55.951 1133-1546/? D/jadon_level: dbm = -99        3G level = 3
05-06 13:08:55.951 1133-1546/? D/NetworkTypeUtils: getNetworkType: type=10
    getNetworkTypeIcon iconId = 2130838720
05-06 13:08:55.954 989-30195/? V/ActivityManager: Broadcast sticky: Intent { act=android.intent.action.SIG_STR flg=0x20000010 (has extras) } ordered=false userid=-1 callerApp=ProcessRecord{5d682d5 989:system/1000}
05-06 13:08:55.999 1133-1133/? D/NetworkController.WifiSignalController: Change in state from: connected=true,enabled=true,level=4,inetCondition=1,iconGroup=IconGroup(Wi-Fi Icons),activityIn=false,activityOut=false,rssi=-56,lastModified=05-06 01:08:55,ssid="SLT-ADSL-716FA"
        to: connected=true,enabled=true,level=4,inetCondition=1,iconGroup=IconGroup(Wi-Fi Icons),activityIn=true,activityOut=true,rssi=-56,lastModified=05-06 01:08:55,ssid="SLT-ADSL-716FA"
05-06 13:08:56.029 329-485/? D/AALService: enableAALEvent: 0 -> 1
05-06 13:08:56.033 329-485/? D/AALService: enableAALEvent: 1 -> 0
    05-06 01:08:56.029 BL= 542,CABC= 256, 
05-06 13:08:56.074 25164-25164/? D/dumpsys: dumpsys start
05-06 13:08:56.125 11433-11433/? D/WebView: evaluateJavascript=AFMA_updateActiveView({"units":[{"afmaVersion":"afma-sdk-a-v12529018.11020000.1","activeViewJSON":{"click_string":"BM1YBiHPsWvvZBdOmoAPAtK7IBgCd7P2n-wYAABABOAHIAQnIAwLgBAOIBc3mi4wFoAZM0ggFCIABEAE,BwsSviHPsWriuA4S9oAOvhIHQBJeF7ZxFAAAAEAEgx4v0SzgAWOf78PmCBGCRmewEsgE2MjIwMzM4LmFuZHJvaWQuY29tLnZpYmVyLnZvaXAuYWRzZW5zZWZvcm1vYmlsZWFwcHMuY29tugEJZ2ZwX2ltYWdlyAEJ2gE-aHR0cDovLzIyMDMzOC5hbmRyb2lkLmNvbS52aWJlci52b2lwLmFkc2Vuc2Vmb3Jtb2JpbGVhcHBzLmNvbS-YAsgBwAIC4AIA6gIfLzY1NjU2MjYzL3Rlc3QvVGltZV9PdXRfMzAweDI1MPgC_NEekAOaCJgD0AWoAwHIAwLgBAHSBQYQvdenqhGQBgGgBjvYBgLYBwDgBx_yBwIgAdIIBwiAARABGAE","is_active_view_immediate_enabled":true,"activeview_cpm_urls":[],"active_experiment_ids":"","activeview_cid":"CAASUeRosf6NHpD3haoD6Hs7FeKRN3UOiX3uvD2Rjlflkl6up87tCfD5lMj3A7hO1JNP3b6C_3ptfeOEU44zDYfwEBdpj3HGy18gKYjKinIQLOpoVw"},"timestamp":489872398,"adFormat":"300x250_as","hashCode":"0307fc59-3858-4be2-9ad6-f286cf9ed0ae","isMraid":true,"isStopped":false,"isPaused":false,"isNative":false,"isScreenOn":true,"appMuted":false,"appVolume":1,"deviceVolume":0.800000011920929,"windowVisibility":8,"isAttachedToWindow":false,"viewBox":{"top":0,"bottom":569,"left":0,"right":320},"adBox":{"top":0,"bottom":0,"left":0,"right":0},"globalVisibleBox":{"top":0,"bottom":0,"left":0,"right":0},"globalVisibleBoxVisible":false,"localVisibleBox":{"top":0,"bottom":0,"left":0,"right":0},"localVisibleBoxVisible":false,"hitBox":{"top":0,"bottom":0,"left":0,"right":0},"screenDensity":1.5,"isVisible":false}]});
05-06 13:08:56.126 11433-11433/? D/WebView: evaluateJavascript=AFMA_updateActiveView({"units":[{"afmaVersion":"afma-sdk-a-v12529018.11020000.1","activeViewJSON":{"click_string":"BM1YBiHPsWvvZBdOmoAPAtK7IBgCd7P2n-wYAABABOAHIAQnIAwLgBAOIBc3mi4wFoAZM0ggFCIABEAE,BwsSviHPsWriuA4S9oAOvhIHQBJeF7ZxFAAAAEAEgx4v0SzgAWOf78PmCBGCRmewEsgE2MjIwMzM4LmFuZHJvaWQuY29tLnZpYmVyLnZvaXAuYWRzZW5zZWZvcm1vYmlsZWFwcHMuY29tugEJZ2ZwX2ltYWdlyAEJ2gE-aHR0cDovLzIyMDMzOC5hbmRyb2lkLmNvbS52aWJlci52b2lwLmFkc2Vuc2Vmb3Jtb2JpbGVhcHBzLmNvbS-YAsgBwAIC4AIA6gIfLzY1NjU2MjYzL3Rlc3QvVGltZV9PdXRfMzAweDI1MPgC_NEekAOaCJgD0AWoAwHIAwLgBAHSBQYQvdenqhGQBgGgBjvYBgLYBwDgBx_yBwIgAdIIBwiAARABGAE","is_active_view_immediate_enabled":true,"activeview_cpm_urls":[],"active_experiment_ids":"","activeview_cid":"CAASUeRosf6NHpD3haoD6Hs7FeKRN3UOiX3uvD2Rjlflkl6up87tCfD5lMj3A7hO1JNP3b6C_3ptfeOEU44zDYfwEBdpj3HGy18gKYjKinIQLOpoVw"},"timestamp":489872398,"adFormat":"300x250_as","hashCode":"0307fc59-3858-4be2-9ad6-f286cf9ed0ae","isMraid":true,"isStopped":false,"isPaused":false,"isNative":false,"isScreenOn":true,"appMuted":false,"appVolume":1,"deviceVolume":0.800000011920929,"windowVisibility":8,"isAttachedToWindow":false,"viewBox":{"top":0,"bottom":569,"left":0,"right":320},"adBox":{"top":0,"bottom":0,"left":0,"right":0},"globalVisibleBox":{"top":0,"bottom":0,"left":0,"right":0},"globalVisibleBoxVisible":false,"localVisibleBox":{"top":0,"bottom":0,"left":0,"right":0},"localVisibleBoxVisible":false,"hitBox":{"top":0,"bottom":0,"left":0,"right":0},"screenDensity":1.5,"isVisible":false}]});
05-06 13:08:56.252 236-7099/? I/MAL-RDS:  (        ru_syssig_hndler,  493) [RDS-I][ru_syssig_hndler] Send Event: 9089 
05-06 13:08:56.272 236-578/? D/MAL-RDS:  (     ru_wsl_poll_wpainfo,  727) [RDS-D][RDS][RU][ru_wsl_poll_wpainfo]socket recv pktlen(48) 
     (rds_ru_ws_rssi_timer_exp,  841) [RDS-D][RU][rds_ru_ws_rssi_timer_expire_hdlr][RDS] get rssi = -56, snr = 9999 
05-06 13:08:56.273 236-578/? I/MAL-RDS:  (          ru_get_netstat, 6371) [RDS-I][RU][ru_get_netstat] netstat <thrghpt, pkterrt>, wifi <295, 0%>, mobile <0, 0%>
     (  rds_ru_wifi_status_ind, 1518) [RDS-I][RU][EVENT_RU_WS_WIFI_STATUS_IND] fgwifi_en:1(no use) i4wifirssi:0xffffffc8 i4wifisnr:0x270f
     (  rds_ru_ims_vops_update, 5726) [RDS-I][RU][rds_ru_ims_vops_update][RDS IMS]IMS VOPS IE is Disabled, Update to RPL<0>:(254,254), <1>:(254,254), <2>:(254,254)
05-06 13:08:56.274 236-578/? I/MAL-RDS:  (          rds_ru_rpl_gen, 5977) [RDS-I][RU][rds_ru_rpl_gen][RDS] Current policy: fgimsolte_en<0>, fgwfc_en<0>, erdspolicy<3>,||Threshold i4wifirssih<-75>, i4wifirssil<-85>, i4wifirssih_ho<-78>, i4wifirssil_ho<-88>, i4wifisnrh<10>, i4wifisnrl<6>||Threshold i4ltersrph<-106>, i4ltersrpm<-111>, i4ltersrpl<-116>, i4ltersrqh<5>, i4ltersrqm<3>, i4ltersrql<1>||Threshold i4utranrscph<-104>, i4utranrscpl<-110>, i4gsmrssih<-94>, i4gsmrssil<-102>||current rds ru status: i4wifirssi<-56>, i4wifisnr<9999>, i4ltersrp<-99>, i4ltersrq<40>, i4utranrscp<-99>, i4gsmrssi<-96>, u4active_ran<262147>||current wifi backhaul : rtp_plr<0>, rtp_jitter<0>, ping_ind<0>||pcscf acc stat : volte<1>, wfc<1> || wifi acc_ctrl:<0>, || current MD stat : MD1 roam <0>, ||Call stat : IR92<0>, IR94<0>, SMS over IP<0>
     (          rds_ru_rpl_gen, 5994) [RDS-I][RU][RDS IMS/MMS][rds_ru_rpl_gen][OP-0] Ori:(254,254)/(1,255) New:(254,254)/(1,255)||[RU][RDS IMS/MMS WIFI]Ori:(254,254)/(1,255) New:(254,254)/(1,255)||[RU][RDS IMS/MMS CELL]Ori:(254,254)/(1,255) New:(254,254)/(1,255)
05-06 13:08:56.307 24973-24973/com.example.babara.apointee D/AndroidRuntime: Shutting down VM
05-06 13:08:56.324 25166-25166/? D/dumpsys: dumpsys start
05-06 13:08:56.336 11433-11433/? D/WebView: evaluateJavascript=AFMA_updateActiveView({"units":[{"afmaVersion":"afma-sdk-a-v12529018.11020000.1","activeViewJSON":{"click_string":"BM1YBiHPsWvvZBdOmoAPAtK7IBgCd7P2n-wYAABABOAHIAQnIAwLgBAOIBc3mi4wFoAZM0ggFCIABEAE,BwsSviHPsWriuA4S9oAOvhIHQBJeF7ZxFAAAAEAEgx4v0SzgAWOf78PmCBGCRmewEsgE2MjIwMzM4LmFuZHJvaWQuY29tLnZpYmVyLnZvaXAuYWRzZW5zZWZvcm1vYmlsZWFwcHMuY29tugEJZ2ZwX2ltYWdlyAEJ2gE-aHR0cDovLzIyMDMzOC5hbmRyb2lkLmNvbS52aWJlci52b2lwLmFkc2Vuc2Vmb3Jtb2JpbGVhcHBzLmNvbS-YAsgBwAIC4AIA6gIfLzY1NjU2MjYzL3Rlc3QvVGltZV9PdXRfMzAweDI1MPgC_NEekAOaCJgD0AWoAwHIAwLgBAHSBQYQvdenqhGQBgGgBjvYBgLYBwDgBx_yBwIgAdIIBwiAARABGAE","is_active_view_immediate_enabled":true,"activeview_cpm_urls":[],"active_experiment_ids":"","activeview_cid":"CAASUeRosf6NHpD3haoD6Hs7FeKRN3UOiX3uvD2Rjlflkl6up87tCfD5lMj3A7hO1JNP3b6C_3ptfeOEU44zDYfwEBdpj3HGy18gKYjKinIQLOpoVw"},"timestamp":489872608,"adFormat":"300x250_as","hashCode":"0307fc59-3858-4be2-9ad6-f286cf9ed0ae","isMraid":true,"isStopped":false,"isPaused":false,"isNative":false,"isScreenOn":true,"appMuted":false,"appVolume":1,"deviceVolume":0.800000011920929,"windowVisibility":8,"isAttachedToWindow":false,"viewBox":{"top":0,"bottom":569,"left":0,"right":320},"adBox":{"top":0,"bottom":0,"left":0,"right":0},"globalVisibleBox":{"top":0,"bottom":0,"left":0,"right":0},"globalVisibleBoxVisible":false,"localVisibleBox":{"top":0,"bottom":0,"left":0,"right":0},"localVisibleBoxVisible":false,"hitBox":{"top":0,"bottom":0,"left":0,"right":0},"screenDensity":1.5,"isVisible":false}]});
05-06 13:08:56.337 11433-11433/? D/WebView: evaluateJavascript=AFMA_updateActiveView({"units":[{"afmaVersion":"afma-sdk-a-v12529018.11020000.1","activeViewJSON":{"click_string":"BM1YBiHPsWvvZBdOmoAPAtK7IBgCd7P2n-wYAABABOAHIAQnIAwLgBAOIBc3mi4wFoAZM0ggFCIABEAE,BwsSviHPsWriuA4S9oAOvhIHQBJeF7ZxFAAAAEAEgx4v0SzgAWOf78PmCBGCRmewEsgE2MjIwMzM4LmFuZHJvaWQuY29tLnZpYmVyLnZvaXAuYWRzZW5zZWZvcm1vYmlsZWFwcHMuY29tugEJZ2ZwX2ltYWdlyAEJ2gE-aHR0cDovLzIyMDMzOC5hbmRyb2lkLmNvbS52aWJlci52b2lwLmFkc2Vuc2Vmb3Jtb2JpbGVhcHBzLmNvbS-YAsgBwAIC4AIA6gIfLzY1NjU2MjYzL3Rlc3QvVGltZV9PdXRfMzAweDI1MPgC_NEekAOaCJgD0AWoAwHIAwLgBAHSBQYQvdenqhGQBgGgBjvYBgLYBwDgBx_yBwIgAdIIBwiAARABGAE","is_active_view_immediate_enabled":true,"activeview_cpm_urls":[],"active_experiment_ids":"","activeview_cid":"CAASUeRosf6NHpD3haoD6Hs7FeKRN3UOiX3uvD2Rjlflkl6up87tCfD5lMj3A7hO1JNP3b6C_3ptfeOEU44zDYfwEBdpj3HGy18gKYjKinIQLOpoVw"},"timestamp":489872608,"adFormat":"300x250_as","hashCode":"0307fc59-3858-4be2-9ad6-f286cf9ed0ae","isMraid":true,"isStopped":false,"isPaused":false,"isNative":false,"isScreenOn":true,"appMuted":false,"appVolume":1,"deviceVolume":0.800000011920929,"windowVisibility":8,"isAttachedToWindow":false,"viewBox":{"top":0,"bottom":569,"left":0,"right":320},"adBox":{"top":0,"bottom":0,"left":0,"right":0},"globalVisibleBox":{"top":0,"bottom":0,"left":0,"right":0},"globalVisibleBoxVisible":false,"localVisibleBox":{"top":0,"bottom":0,"left":0,"right":0},"localVisibleBoxVisible":false,"hitBox":{"top":0,"bottom":0,"left":0,"right":0},"screenDensity":1.5,"isVisible":false}]});

    --------- beginning of crash
05-06 13:08:56.350 24973-24973/com.example.babara.apointee E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.babara.apointee, PID: 24973
    android.os.NetworkOnMainThreadException
        at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1318)
        at java.net.Inet6AddressImpl.lookupHostByName(Inet6AddressImpl.java:86)
        at java.net.Inet6AddressImpl.lookupAllHostAddr(Inet6AddressImpl.java:74)
        at java.net.InetAddress.getAllByName(InetAddress.java:757)
        at com.android.okhttp.internal.Network$1.resolveInetAddresses(Network.java:29)
        at com.android.okhttp.internal.http.RouteSelector.resetNextInetSocketAddress(RouteSelector.java:187)
        at com.android.okhttp.internal.http.RouteSelector.nextProxy(RouteSelector.java:156)
        at com.android.okhttp.internal.http.RouteSelector.next(RouteSelector.java:98)
        at com.android.okhttp.internal.http.HttpEngine.createNextConnection(HttpEngine.java:372)
        at com.android.okhttp.internal.http.HttpEngine.connect(HttpEngine.java:355)
        at com.android.okhttp.internal.http.HttpEngine.sendRequest(HttpEngine.java:273)
        at com.android.okhttp.internal.huc.HttpURLConnectionImpl.execute(HttpURLConnectionImpl.java:474)
        at com.android.okhttp.internal.huc.HttpURLConnectionImpl.connect(HttpURLConnectionImpl.java:126)

that server address can be manually accessed through the browser though. And I have given uses permission for INTERNET and ACCESS_NETWORK_STATE.

Can someone point me out the issue here, please. (Currently using Device with Android Version 7.0 for testing)

android {
    compileSdkVersion 27
    defaultConfig {
        applicationId "com.example.babara.apointee"
        minSdkVersion 15
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    ...
}

dependencies {
    implementation 'com.android.support:appcompat-v7:27.1.1'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.1'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.1'
    implementation files('libs/json-simple-1.1.jar')
}

score 2 · Accepted Answer · answered May 06 '18 at 09:40

You are trying to perform network operations on the main thread. You need to write that code in AsyncTask

private class NetworkOperation extends AsyncTask<String, Void, String> {
    @Override
    protected String doInBackground(String... params) {
        //Add your network code here
    }      

    @Override
    protected void onPostExecute(String result) {

    }
}

And then in your onCreate(), add:

new NetworkOperation.execute("");

score 1 · Answer 2 · answered May 06 '18 at 09:35

The NetworkOnMainThread Exception is because you are trying to perform the network operation in the main thread(which is not valid).

In order to perform the network operation, you must use AsyncTask.

Here it can be the similar topic and the solution you are looking for.

HttpURLConnection connect() method fails and crash

2 Answers2