fix some "serialVersionUID" warnings

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@592841 13f79535-47bb-0310-9956-ffa450edef68

src/main/org/apache/tools/ant/BuildEvent.java

@@ -29,6 +29,8 @@ import java.util.EventObject;
  */
 public class BuildEvent extends EventObject {
 
+    private static final long serialVersionUID = 4538050075952288486L;
+
     /** Project which emitted the event. */
     private Project project;
     /** Target which emitted the event, if specified. */

src/main/org/apache/tools/ant/BuildException.java

@@ -25,6 +25,8 @@ import java.io.PrintWriter;
  */
 public class BuildException extends RuntimeException {
 
+    private static final long serialVersionUID = -5419014565354664240L;
+
     /** Exception that might have caused this one. */
     private Throwable cause;
 

src/main/org/apache/tools/ant/ExitException.java

@@ -26,6 +26,8 @@ package org.apache.tools.ant;
  */
 public class ExitException extends SecurityException {
 
+    private static final long serialVersionUID = 2772487854280543363L;
+
     /** Status code */
     private int status;
 

src/main/org/apache/tools/ant/ExitStatusException.java

@@ -24,6 +24,8 @@ package org.apache.tools.ant;
  */
 public class ExitStatusException extends BuildException {
 
+    private static final long serialVersionUID = 7760846806886585968L;
+
     /** Status code */
     private int status;
 

src/main/org/apache/tools/ant/taskdefs/optional/EchoProperties.java

@@ -387,6 +387,7 @@ public class EchoProperties extends Task {
         final List keyList = new ArrayList(allProps.keySet());
         Collections.sort(keyList);
         Properties props = new Properties() {
+            private static final long serialVersionUID = 5090936442309201654L;
             public Enumeration keys() {
                 return CollectionUtils.asEnumeration(keyList.iterator());
             }

src/main/org/apache/tools/ant/taskdefs/optional/junit/DOMUtil.java

@@ -86,6 +86,8 @@ public final class DOMUtil {
 
     /** custom implementation of a nodelist */
     public static class NodeListImpl extends Vector implements NodeList {
+        private static final long serialVersionUID = 3175749150080946423L;
+
         /**
          * Get the number of nodes in the list.
          * @return the length of the list.

src/main/org/apache/tools/ant/taskdefs/optional/testing/BuildTimeoutException.java

@@ -30,6 +30,7 @@ import org.apache.tools.ant.Location;
 
 public class BuildTimeoutException extends BuildException {
 
+    private static final long serialVersionUID = -8057644603246297562L;
 
     /**
      * Constructs a build exception with no descriptive information.

src/main/org/apache/tools/ant/util/IdentityStack.java

@@ -25,6 +25,8 @@ import java.util.Stack;
  */
 public class IdentityStack extends Stack {
 
+    private static final long serialVersionUID = -5555522620060077046L;
+
     /**
      * Get an IdentityStack containing the contents of the specified Stack.
      * @param s the Stack to copy; ignored if null.