Fix jardiff's Tools.isAccessChange(..): Differentiate between Class, Field and Method and apply all rules of the Java Language Specification

Class, Field and Methods have different binary backward compatibility rules
as specified in the Java Language Specification, Java SE 7 Edition:
  - http://docs.oracle.com/javase/specs/jls/se7/html/jls-13.html

For Field 'volatile' the Java Language Specification, first edition has been used:
  - http://www.wsu.edu/UNIX_Systems/java/langspec-1.0/13.doc.html#45194

For each type separate method have been created, i.e. Tools.is<Type>AccessChange().
Each new method has the rules referenced and partially copied into the method
for better documentation.

The now deprecated method Tools.isAccessChange(..) calls Tools.isClassAccessChange(..)
and shall be removed.

Unit test ToolsTest has been expanded for each type and its rules.

1 files changed, 12 insertions, 12 deletions

diff --git a/api/src/main/java/org/osjava/jardiff/PublicDiffCriteria.java b/api/src/main/java/org/osjava/jardiff/PublicDiffCriteria.java
index 9940255..90fb382 100644
--- a/api/src/main/java/org/osjava/jardiff/PublicDiffCriteria.java
+++ b/api/src/main/java/org/osjava/jardiff/PublicDiffCriteria.java
@@ -38,7 +38,7 @@ public class PublicDiffCriteria implements DiffCriteria
     public boolean validClass(ClassInfo info) {
         return !info.isSynthetic() && info.isPublic();
     }
-    
+
     /**
      * Check if a method is valid.
      * If the method is not synthetic and public, return true.
@@ -49,7 +49,7 @@ public class PublicDiffCriteria implements DiffCriteria
     public boolean validMethod(MethodInfo info) {
         return !info.isSynthetic() && info.isPublic();
     }
-    
+
     /**
      * Check if a field is valid.
      * If the method is not synthetic and public, return true.
@@ -60,7 +60,7 @@ public class PublicDiffCriteria implements DiffCriteria
     public boolean validField(FieldInfo info) {
         return !info.isSynthetic() && info.isPublic();
     }
-    
+
     /**
      * Check if there is a change between two versions of a class.
      * Returns true if the access flags differ, or if the superclass differs
@@ -71,7 +71,7 @@ public class PublicDiffCriteria implements DiffCriteria
      * @return True if the classes differ, false otherwise.
      */
     public boolean differs(ClassInfo oldInfo, ClassInfo newInfo) {
-        if (Tools.isAccessChange(oldInfo.getAccess(), newInfo.getAccess()))
+        if (Tools.isClassAccessChange(oldInfo.getAccess(), newInfo.getAccess()))
             return true;
         // Yes classes can have a null supername, e.g. java.lang.Object !
         if(oldInfo.getSupername() == null) {
@@ -81,15 +81,15 @@ public class PublicDiffCriteria implements DiffCriteria
         } else if (!oldInfo.getSupername().equals(newInfo.getSupername())) {
             return true;
         }
-        Set<String> oldInterfaces
+        final Set<String> oldInterfaces
             = new HashSet(Arrays.asList(oldInfo.getInterfaces()));
-        Set<String> newInterfaces
+        final Set<String> newInterfaces
             = new HashSet(Arrays.asList(newInfo.getInterfaces()));
         if (!oldInterfaces.equals(newInterfaces))
             return true;
         return false;
     }
-    
+
     /**
      * Check if there is a change between two versions of a method.
      * Returns true if the access flags differ, or if the thrown
@@ -100,23 +100,23 @@ public class PublicDiffCriteria implements DiffCriteria
      * @return True if the methods differ, false otherwise.
      */
     public boolean differs(MethodInfo oldInfo, MethodInfo newInfo) {
-        if (Tools.isAccessChange(oldInfo.getAccess(), newInfo.getAccess()))
+        if (Tools.isMethodAccessChange(oldInfo.getAccess(), newInfo.getAccess()))
             return true;
         if (oldInfo.getExceptions() == null
             || newInfo.getExceptions() == null) {
             if (oldInfo.getExceptions() != newInfo.getExceptions())
                 return true;
         } else {
-            Set<String> oldExceptions
+            final Set<String> oldExceptions
                 = new HashSet(Arrays.asList(oldInfo.getExceptions()));
-            Set<String> newExceptions
+            final Set<String> newExceptions
                 = new HashSet(Arrays.asList(newInfo.getExceptions()));
             if (!oldExceptions.equals(newExceptions))
                 return true;
         }
         return false;
     }
-    
+
     /**
      * Check if there is a change between two versions of a field.
      * Returns true if the access flags differ, or if the inital value
@@ -127,7 +127,7 @@ public class PublicDiffCriteria implements DiffCriteria
      * @return True if the fields differ, false otherwise.
      */
     public boolean differs(FieldInfo oldInfo, FieldInfo newInfo) {
-        if (Tools.isAccessChange(oldInfo.getAccess(), newInfo.getAccess()))
+        if (Tools.isFieldAccessChange(oldInfo.getAccess(), newInfo.getAccess()))
             return true;
         if (oldInfo.getValue() == null || newInfo.getValue() == null) {
             if (oldInfo.getValue() != newInfo.getValue())