Merge branch 'enable-pmd-java-basic' into 'master'

Enable PMD java-basic

This is the fixes necessary to enable PMD's `java-basic` ruleset.  I think there will be a few rules in there that will largely be annoying, so we'll need to ultimately decide whether to use `// NOPMD` or just specify the rules we want from `java-basic`.

See merge request !280

app/src/main/java/org/fdroid/fdroid/AndroidXMLDecompress.java

@@ -89,7 +89,8 @@ public class AndroidXMLDecompress {
         }
         int offset = xmlTagOffset;
 
-        while (offset < binaryXml.length) {
+        // we only need the first <manifest> start tag
+        if (offset < binaryXml.length) {
             int tag0 = littleEndianWord(binaryXml, offset);
 
             if (tag0 == START_TAG) {
@@ -114,8 +115,6 @@ public class AndroidXMLDecompress {
                 }
                 return attributes;
             }
-            // we only need the first <manifest> start tag
-            break;
         }
         return new HashMap<>(0);
     }

app/src/main/java/org/fdroid/fdroid/localrepo/peers/BluetoothPeer.java

@@ -34,6 +34,11 @@ public class BluetoothPeer implements Peer {
         return peer != null && peer instanceof BluetoothPeer && ((BluetoothPeer) peer).device.getAddress().equals(device.getAddress());
     }
 
+    @Override
+    public int hashCode() {
+        return device.getAddress().hashCode();
+    }
+
     @Override
     public String getRepoAddress() {
         return "bluetooth://" + device.getAddress().replace(':', '-') + "/fdroid/repo";

app/src/main/java/org/fdroid/fdroid/localrepo/peers/BonjourPeer.java

@@ -36,6 +36,11 @@ public class BonjourPeer extends WifiPeer {
         return false;
     }
 
+    @Override
+    public int hashCode() {
+        return getFingerprint().hashCode();
+    }
+
     @Override
     public String getRepoAddress() {
         return serviceInfo.getRepoAddress();

app/src/main/java/org/fdroid/fdroid/net/LocalHTTPD.java

@@ -265,7 +265,10 @@ public class LocalHTTPD extends NanoHTTPD {
                             return (int) dataLen;
                         }
                     };
-                    fis.skip(startFrom);
+                    long skipped = fis.skip(startFrom);
+                    if (skipped != startFrom) {
+                        throw new IOException("unable to skip the required " + startFrom + " bytes.");
+                    }
 
                     res = createResponse(Response.Status.PARTIAL_CONTENT, mime, fis);
                     res.addHeader("Content-Length", String.valueOf(dataLen));

app/src/main/java/org/fdroid/fdroid/net/bluetooth/BluetoothServer.java

@@ -303,7 +303,10 @@ public class BluetoothServer extends Thread {
                                 return (int) dataLen;
                             }
                         };
-                        fis.skip(startFrom);
+                        long skipped = fis.skip(startFrom);
+                        if (skipped != startFrom) {
+                            throw new IOException("unable to skip the required " + startFrom + " bytes.");
+                        }
 
                         res = createResponse(NanoHTTPD.Response.Status.PARTIAL_CONTENT, mime, fis);
                         res.addHeader("Content-Length", String.valueOf(dataLen));

app/src/main/java/org/fdroid/fdroid/views/swap/SwapWorkflowActivity.java

@@ -740,7 +740,7 @@ public class SwapWorkflowActivity extends AppCompatActivity {
 
         public void logStatus() {
 
-            if (true) return;
+            if (true) return; // NOPMD
 
             String message = "";
             if (service == null) {

config/pmd/rules.xml

@@ -5,7 +5,9 @@
         xsi:schemaLocation="http://pmd.sf.net/ruleset/1.0.0 http://pmd.sf.net/ruleset_xml_schema.xsd"
         xsi:noNamespaceSchemaLocation="http://pmd.sf.net/ruleset_xml_schema.xsd">
 
-    <!--<rule ref="rulesets/java/basic.xml"/>-->
+    <rule ref="rulesets/java/basic.xml">
+        <exclude name="CollapsibleIfStatements"/> <!--sometimes forces hard to read code-->
+    </rule>
     <rule ref="rulesets/java/unusedcode.xml"/>
     <rule ref="rulesets/java/android.xml"/>
     <rule ref="rulesets/java/clone.xml"/>