fixed potential memory leaks

ch.psi.fdaq/src/main/java/ch/psi/fdaq/FdaqService.java

@@ -50,12 +50,18 @@ public class FdaqService {
 			
 			@Override
 			public void run() {
+				
+				PrintWriter writer = null;
+				Socket echoSocket = null;
+				DataOutputStream out = null;
+				DataInputStream in = null;
+				
 				try {
 					FdaqConfiguration config = FdaqConfiguration.getInstance();
 					stopAcquisition = false;
-					Socket echoSocket = new Socket(config.getHostname(), config.getPort());
-					DataOutputStream out = new DataOutputStream(echoSocket.getOutputStream());
-					DataInputStream in = new DataInputStream(echoSocket.getInputStream());
+					echoSocket = new Socket(config.getHostname(), config.getPort());
+					out = new DataOutputStream(echoSocket.getOutputStream());
+					in = new DataInputStream(echoSocket.getInputStream());
 
 					int nMessages = config.getNelements();
 
@@ -70,7 +76,7 @@ public class FdaqService {
 
 					
 					// open file and write
-					try(PrintWriter writer = new PrintWriter(new BufferedWriter(new FileWriter(file)))){
+					writer = new PrintWriter(new BufferedWriter(new FileWriter(file)));
 						
 						writer.println("# a" + "\t" + "b1" + "\t" + "b2" + "\t" + "c1" + "\t" + "c2" + "\t" + "d");
 					
@@ -97,8 +103,8 @@ public class FdaqService {
 //							System.out.println(a + " " + b1 + " " + b2 + " " + c1 + " " + c2 + " " + d);
 							writer.println(a + "\t" + b1 + "\t" + b2 + "\t" + c1 + "\t" + c2 + "\t" + d);
 						}
-					}
-
+						
+					writer.close();
 					out.close();
 					in.close();
 					echoSocket.close();
@@ -107,6 +113,16 @@ public class FdaqService {
 						logger.log(Level.SEVERE, "", e);
 					}
 				}
+				finally{
+					try{
+						writer.close();
+						out.close();
+						in.close();
+						echoSocket.close();
+					} catch (IOException e) {
+						// Ignore because not relevant at this stage
+					}
+				}
 			}
 		});
 		t.start();