make the fields in ExecRes final

src/de/uni_passau/fim/seibt/gitwrapper/process/ProcessExecutor.java

@@ -25,10 +25,16 @@ public class ProcessExecutor {
     /**
      * The result of a process execution.
      */
-    public static class ExecRes {
-        public int exitCode;
-        public String stdOut;
-        public String stdErr;
+    public static final class ExecRes {
+        public final int exitCode;
+        public final String stdOut;
+        public final String stdErr;
+
+        private ExecRes(int exitCode, String stdOut, String stdErr) {
+            this.exitCode = exitCode;
+            this.stdOut = stdOut;
+            this.stdErr = stdErr;
+        }
     }
 
     /**
@@ -70,25 +76,28 @@ public class ProcessExecutor {
         LOG.fine(() -> String.format("Executing '%s' in '%s'.", cmd, builder.directory().getAbsolutePath()));
 
         try {
-            ExecRes res = new ExecRes();
             Process p = builder.start();
 
-            res.stdOut = IOUtils.toString(p.getInputStream(), StandardCharsets.UTF_8).trim();
-            res.stdErr = IOUtils.toString(p.getErrorStream(), StandardCharsets.UTF_8).trim();
+            String stdOut = IOUtils.toString(p.getInputStream(), StandardCharsets.UTF_8).trim();
+            String stdErr = IOUtils.toString(p.getErrorStream(), StandardCharsets.UTF_8).trim();
 
             IOUtils.closeQuietly(p.getInputStream());
             IOUtils.closeQuietly(p.getErrorStream());
             IOUtils.closeQuietly(p.getOutputStream());
 
+            int exitCode;
+            
             try {
-                res.exitCode = p.waitFor();
+                exitCode = p.waitFor();
             } catch (InterruptedException e) {
                 LOG.log(WARNING, e, () -> String.format("Interrupted while waiting for '%s' to finish.", cmd));
 
                 p.destroyForcibly();
-                res.exitCode = EXIT_FAIL;
+                exitCode = EXIT_FAIL;
             }
 
+            ExecRes res = new ExecRes(exitCode, stdOut, stdErr);
+
             LOG.fine(() -> String.format("Execution of '%s' returned exit code %d.", cmd, res.exitCode));
 
             if (res.stdOut.isEmpty()) {