replaced 4-line regex blocks with call to equivalent method; removed unecessary try-catch blocks surrounding them: regex methods don't throw runtime exceptions

.idea/gradle.xml

@@ -6,7 +6,7 @@
         <option name="distributionType" value="LOCAL" />
         <option name="externalProjectPath" value="$PROJECT_DIR$" />
         <option name="gradleHome" value="$APPLICATION_HOME_DIR$/gradle/gradle-2.4" />
-        <option name="gradleJvm" value="1.8" />
+        <option name="gradleJvm" value="1.7" />
         <option name="modules">
           <set>
             <option value="$PROJECT_DIR$" />
@@ -16,4 +16,4 @@
       </GradleProjectSettings>
     </option>
   </component>
-</project>
+</project>

.idea/misc.xml

@@ -37,10 +37,10 @@
     <ConfirmationsSetting value="0" id="Add" />
     <ConfirmationsSetting value="0" id="Remove" />
   </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_7" default="true" assert-keyword="true" jdk-15="true" project-jdk-name="1.8" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_7" default="true" assert-keyword="true" jdk-15="true" project-jdk-name="1.7" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/build/classes" />
   </component>
   <component name="ProjectType">
     <option name="id" value="Android" />
   </component>
-</project>
+</project>

app/app.iml

@@ -92,12 +92,12 @@
     </content>
     <orderEntry type="jdk" jdkName="Android API 23 Platform" jdkType="Android SDK" />
     <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="library" exported="" name="rhino-1.7.7" level="project" />
     <orderEntry type="library" exported="" name="recyclerview-v7-23.1.0" level="project" />
+    <orderEntry type="library" exported="" name="support-annotations-23.1.0" level="project" />
+    <orderEntry type="library" exported="" name="appcompat-v7-23.1.0" level="project" />
+    <orderEntry type="library" exported="" name="design-23.1.0" level="project" />
     <orderEntry type="library" exported="" name="jsoup-1.8.3" level="project" />
     <orderEntry type="library" exported="" name="support-v4-23.1.0" level="project" />
-    <orderEntry type="library" exported="" name="rhino-1.7.7" level="project" />
-    <orderEntry type="library" exported="" name="design-23.1.0" level="project" />
-    <orderEntry type="library" exported="" name="appcompat-v7-23.1.0" level="project" />
-    <orderEntry type="library" exported="" name="support-annotations-23.1.0" level="project" />
   </component>
 </module>

app/src/main/java/org/schabi/newpipe/youtube/YoutubeExtractor.java

@@ -3,6 +3,7 @@ package org.schabi.newpipe.youtube;
 import android.util.Log;
 import android.util.Xml;
 
+import org.json.JSONException;
 import org.json.JSONObject;
 import org.jsoup.Jsoup;
 import org.jsoup.nodes.Document;
@@ -141,14 +142,7 @@ public class YoutubeExtractor implements Extractor {
 
         Document doc = Jsoup.parse(site, siteUrl);
 
-        try {
+        videoInfo.id = matchGroup1("v=([0-9a-zA-Z]*)", siteUrl);
-            Pattern p = Pattern.compile("v=([0-9a-zA-Z]*)");
-            Matcher m = p.matcher(siteUrl);
-            m.find();
-            videoInfo.id = m.group(1);
-        } catch (Exception e) {
-            e.printStackTrace();
-        }
 
         videoInfo.age_limit = 0;
         videoInfo.webpage_url = siteUrl;
@@ -160,16 +154,14 @@ public class YoutubeExtractor implements Extractor {
         JSONObject ytAssets = null;
         String dashManifest;
         {
-            Pattern p = Pattern.compile("ytplayer.config\\s*=\\s*(\\{.*?\\});");
+            String jsonString = matchGroup1("ytplayer.config\\s*=\\s*(\\{.*?\\});", site);
-            Matcher m = p.matcher(site);
-            m.find();
 
             try {
-                playerArgs = (new JSONObject(m.group(1)))
+                JSONObject jsonObj = new JSONObject(jsonString);
-                        .getJSONObject("args");
+                playerArgs = jsonObj.getJSONObject("args");
-                ytAssets = (new JSONObject(m.group(1)))
+                ytAssets = jsonObj.getJSONObject("assets");
-                        .getJSONObject("assets");
+            }
-            }catch (Exception e) {
+            catch (Exception e) {
                 e.printStackTrace();
                 // If we fail in this part the video is most likely not available.
                 // Determining why is done later.
@@ -263,15 +255,9 @@ public class YoutubeExtractor implements Extractor {
         // upload date
         videoInfo.upload_date = doc.select("strong[class=\"watch-time-text\"").first()
                 .text();
+
         // Try to only use date not the text around it
-        try {
+        videoInfo.upload_date = matchGroup1("([0-9.]*$)", videoInfo.upload_date);
-            Pattern p = Pattern.compile("([0-9.]*$)");
-            Matcher m = p.matcher(videoInfo.upload_date);
-            m.find();
-            videoInfo.upload_date = m.group(1);
-        } catch (Exception e) {
-            e.printStackTrace();
-        }
 
         // description
         videoInfo.description = doc.select("p[id=\"eow-description\"]").first()
@@ -324,14 +310,10 @@ public class YoutubeExtractor implements Extractor {
         if(!dashManifest.contains("/signature/")) {
             String encryptedSig = "";
             String decryptedSig;
-            try {
+
-                Pattern p = Pattern.compile("/s/([a-fA-F0-9\\.]+)");
+            //regex methods do not throw runtime exceptions, if their arguments are valid
-                Matcher m = p.matcher(dashManifest);
+            encryptedSig = matchGroup1("/s/([a-fA-F0-9\\.]+)", dashManifest);
-                m.find();
+
-                encryptedSig = m.group(1);
-            } catch (Exception e) {
-                e.printStackTrace();
-            }
             decryptedSig = decryptSignature(encryptedSig, decryptoinCode);
             dashManifest = dashManifest.replace("/s/" + encryptedSig, "/signature/" + decryptedSig);
         }
@@ -396,10 +378,7 @@ public class YoutubeExtractor implements Extractor {
         info.webpage_url = li.select("a[class*=\"content-link\"]").first()
                 .attr("abs:href");
         try {
-            Pattern p = Pattern.compile("v=([0-9a-zA-Z-]*)");
+            info.id = matchGroup1("v=([0-9a-zA-Z-]*)", info.webpage_url);
-            Matcher m = p.matcher(info.webpage_url);
-            m.find();
-            info.id=m.group(1);
         } catch (Exception e) {
             e.printStackTrace();
         }
@@ -446,27 +425,15 @@ public class YoutubeExtractor implements Extractor {
         String decryptionCode;
 
         try {
-            Pattern p = Pattern.compile("\\.sig\\|\\|([a-zA-Z0-9$]+)\\(");
+            decryptionFuncName = matchGroup1("\\.sig\\|\\|([a-zA-Z0-9$]+)\\(", playerCode);
-            Matcher m = p.matcher(playerCode);
-            m.find();
-            decryptionFuncName = m.group(1);
 
             String functionPattern = "(function " + decryptionFuncName.replace("$", "\\$") + "\\([a-zA-Z0-9_]*\\)\\{.+?\\})";
-            p = Pattern.compile(functionPattern);
+            decryptionFunc = matchGroup1(functionPattern, playerCode);
-            m = p.matcher(playerCode);
-            m.find();
-            decryptionFunc = m.group(1);
 
-            p = Pattern.compile(";([A-Za-z0-9_\\$]{2})\\...\\(");
+            helperObjectName = matchGroup1(";([A-Za-z0-9_\\$]{2})\\...\\(", decryptionFunc);
-            m = p.matcher(decryptionFunc);
-            m.find();
-            helperObjectName = m.group(1);
 
             String helperPattern = "(var " + helperObjectName.replace("$", "\\$") + "=\\{.+?\\}\\};)function";
-            p = Pattern.compile(helperPattern);
+            helperObject = matchGroup1(helperPattern, playerCode);
-            m = p.matcher(playerCode);
-            m.find();
-            helperObject = m.group(1);
 
         } catch (Exception e) {
             e.printStackTrace();
@@ -493,4 +460,11 @@ public class YoutubeExtractor implements Extractor {
         Context.exit();
         return result.toString();
     }
+
+    private String matchGroup1(String pattern, String input) {
+        Pattern pat = Pattern.compile(pattern);
+        Matcher mat = pat.matcher(input);
+        mat.find();
+        return mat.group(1);
+    }
 }