Cleanup the code

- [x] - Use try-with-resource
- [x] - squash similar exceptions
- [x] - Fix confusing reflection specification in EnvInjectActionRetriever

src/main/java/org/jenkinsci/lib/envinject/EnvInjectAction.java

@@ -3,7 +3,6 @@
 import com.google.common.collect.Maps;
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import hudson.model.AbstractBuild;
-import hudson.model.Job;
 import hudson.model.Run;
 import org.apache.commons.collections.map.UnmodifiableMap;
 import org.jenkinsci.lib.envinject.service.EnvInjectSavable;
@@ -138,7 +137,7 @@ private Object writeReplace() throws ObjectStreamException {
 
             Map<String, String> toWrite = getEnvMap();
             if (toWrite == null) {
-                toWrite = Collections.<String, String>emptyMap();
+                toWrite = Collections.emptyMap();
             }
 
             if (build == null && rootDir == null) {

src/main/java/org/jenkinsci/lib/envinject/service/EnvInjectActionRetriever.java

@@ -12,6 +12,8 @@
 import org.kohsuke.accmod.Restricted;
 import org.kohsuke.accmod.restrictions.NoExternalUse;
 
+import javax.annotation.Nonnull;
+
 /**
  * @author Gregory Boissinot
  * @deprecated The actual version of this API class is located in EnvInject API Plugin
@@ -23,15 +25,15 @@ public class EnvInjectActionRetriever {
     //Returns the abstract class Action due to a class loading issue
     //with EnvInjectAction subclasses. Subclasses cannot be casted from
     //all point of Jenkins (classes are not loaded in some points)
-    public Action getEnvInjectAction(AbstractBuild<?, ?> build) {
+    public Action getEnvInjectAction(@Nonnull AbstractBuild<?, ?> build) {
         List<Action> actions;
         if (build == null) {
             throw new NullPointerException("A build object must be set.");
         }
         try {
             Class<?> matrixClass = Class.forName("hudson.matrix.MatrixRun");
             if (matrixClass.isInstance(build)) {
-                Method method = matrixClass.getMethod("getParentBuild", null);
+                Method method = matrixClass.getMethod("getParentBuild");
                 Object object = method.invoke(build);
                 if (object instanceof AbstractBuild<?, ?>) {
                     build = (AbstractBuild<?, ?>) object;
@@ -41,9 +43,7 @@ public Action getEnvInjectAction(AbstractBuild<?, ?> build) {
             LOGGER.log(Level.FINEST, "hudson.matrix.MatrixRun is not installed", e);
         } catch (NoSuchMethodException e) {
             LOGGER.log(Level.WARNING, "The method getParentBuild does not exist for hudson.matrix.MatrixRun", e);
-        } catch (IllegalAccessException e) {
-            LOGGER.log(Level.WARNING, "There was a problem in the invocation of getParentBuild in hudson.matrix.MatrixRun", e);
-        } catch (InvocationTargetException e) {
+        } catch (IllegalAccessException | InvocationTargetException e) {
             LOGGER.log(Level.WARNING, "There was a problem in the invocation of getParentBuild in hudson.matrix.MatrixRun", e);
         }
         actions = build.getActions();

src/main/java/org/jenkinsci/lib/envinject/service/EnvInjectDetector.java

@@ -3,7 +3,6 @@
 import hudson.Plugin;
 import hudson.model.AbstractBuild;
 import hudson.model.Action;
-import hudson.model.Hudson;
 import jenkins.model.Jenkins;
 import org.kohsuke.accmod.Restricted;
 import org.kohsuke.accmod.restrictions.NoExternalUse;

src/main/java/org/jenkinsci/lib/envinject/service/EnvInjectSavable.java

@@ -31,57 +31,36 @@ public Map<String, String> getEnvironment(File envInjectBaseDir) throws EnvInjec
             throw new NullPointerException("A base directory of the envinject file must be set.");
         }
 
-        FileReader fileReader = null;
-        try {
-            File f = new File(envInjectBaseDir, ENVINJECT_TXT_FILENAME);
-            if (!f.exists()) {
-                return null;
-            }
-            fileReader = new FileReader(f);
-            final Map<String, String> result = new HashMap<String, String>();
+        File f = new File(envInjectBaseDir, ENVINJECT_TXT_FILENAME);
+        if (!f.exists()) {
+            return null;
+        }
+
+        try(FileReader fileReader = new FileReader(f)) {
+            final Map<String, String> result = new HashMap<>();
             fromTxt(fileReader, result);
             return result;
-        } catch (FileNotFoundException fne) {
+        } catch (IOException fne) {
             throw new EnvInjectException(fne);
-        } finally {
-            if (fileReader != null) {
-                try {
-                    fileReader.close();
-                } catch (IOException ioe) {
-                    throw new EnvInjectException(ioe);
-                }
-            }
         }
     }
 
     @SuppressFBWarnings(value = "DM_DEFAULT_ENCODING", justification = "Deprecated class")
     public void saveEnvironment(@Nonnull File rootDir,@Nonnull Map<String, String> envMap) throws EnvInjectException {
-        FileWriter fileWriter = null;
-        try {
-            File f = new File(rootDir, ENVINJECT_TXT_FILENAME);
-            fileWriter = new FileWriter(f);
-            Map<String, String> map2Write = new TreeMap<String, String>();
+
+        File f = new File(rootDir, ENVINJECT_TXT_FILENAME);
+        try(FileWriter fileWriter = new FileWriter(f)) {
+            Map<String, String> map2Write = new TreeMap<>();
             map2Write.putAll(envMap);
             toTxt(map2Write, fileWriter);
-        } catch (FileNotFoundException fne) {
-            throw new EnvInjectException(fne);
         } catch (IOException ioe) {
             throw new EnvInjectException(ioe);
-        } finally {
-            if (fileWriter != null) {
-                try {
-                    fileWriter.close();
-                } catch (IOException ioe) {
-                    throw new EnvInjectException(ioe);
-                }
-            }
         }
     }
 
     private void fromTxt(FileReader fileReader, Map<String, String> result) throws EnvInjectException {
-        BufferedReader bufferedReader = new BufferedReader(fileReader);
         String line;
-        try {
+        try(BufferedReader bufferedReader = new BufferedReader(fileReader)) {
             while ((line = bufferedReader.readLine()) != null) {
                 StringTokenizer tokenizer = new StringTokenizer(line, TOKEN);
                 int tokens = tokenizer.countTokens();
@@ -91,14 +70,6 @@ private void fromTxt(FileReader fileReader, Map<String, String> result) throws E
             }
         } catch (IOException ioe) {
             throw new EnvInjectException(ioe);
-        } finally {
-            if (bufferedReader != null) {
-                try {
-                    bufferedReader.close();
-                } catch (IOException ioe) {
-                    throw new EnvInjectException(ioe);
-                }
-            }
         }
     }
 

src/main/java/org/jenkinsci/lib/envinject/service/EnvVarsResolver.java

@@ -69,11 +69,7 @@ public Map<String, String> getEnVars(AbstractBuild build) throws EnvInjectExcept
             try {
                 Method method = envInjectAction.getClass().getMethod("getEnvMap");
                 return (Map<String, String>) method.invoke(envInjectAction);
-            } catch (NoSuchMethodException e) {
-                throw new EnvInjectException(e);
-            } catch (InvocationTargetException e) {
-                throw new EnvInjectException(e);
-            } catch (IllegalAccessException e) {
+            } catch (NoSuchMethodException | InvocationTargetException | IllegalAccessException e) {
                 throw new EnvInjectException(e);
             }
         }
@@ -217,10 +213,8 @@ private Map<String, String> gatherEnvVarsNode(@Nonnull AbstractProject project,
 
             return envVars;
 
-        } catch (IOException ioe) {
+        } catch (IOException | InterruptedException ioe) {
             throw new EnvInjectException(ioe);
-        } catch (InterruptedException ie) {
-            throw new EnvInjectException(ie);
         }
     }