[java] Treat annotation members as public static final

- This fixes #215
 - I created a new method so we didn't change public APIs

pmd-java/src/main/java/net/sourceforge/pmd/lang/java/ast/ASTFieldDeclaration.java

@@ -53,7 +53,7 @@ public class ASTFieldDeclaration extends AbstractJavaAccessTypeNode implements D
 
     @Override
     public boolean isFinal() {
-        if (isInterfaceMember()) {
+        if (isAnnotationMember() || isInterfaceMember()) {
             return true;
         }
         return super.isFinal();
@@ -61,7 +61,7 @@ public class ASTFieldDeclaration extends AbstractJavaAccessTypeNode implements D
 
     @Override
     public boolean isPrivate() {
-        if (isInterfaceMember()) {
+        if (isAnnotationMember() || isInterfaceMember()) {
             return false;
         }
         return super.isPrivate();
@@ -69,7 +69,7 @@ public class ASTFieldDeclaration extends AbstractJavaAccessTypeNode implements D
 
     @Override
     public boolean isPackagePrivate() {
-        if (isInterfaceMember()) {
+        if (isAnnotationMember() || isInterfaceMember()) {
             return false;
         }
         return super.isPackagePrivate();
@@ -77,12 +77,19 @@ public class ASTFieldDeclaration extends AbstractJavaAccessTypeNode implements D
 
     @Override
     public boolean isProtected() {
-        if (isInterfaceMember()) {
+        if (isAnnotationMember() || isInterfaceMember()) {
             return false;
         }
         return super.isProtected();
     }
 
+    public boolean isAnnotationMember() {
+        if (jjtGetParent().jjtGetParent() instanceof ASTAnnotationTypeBody) {
+            return true;
+        }
+        return false;
+    }
+
     public boolean isInterfaceMember() {
         if (jjtGetParent().jjtGetParent() instanceof ASTEnumBody) {
             return false;

pmd-java/src/test/java/net/sourceforge/pmd/lang/java/ast/ASTFieldDeclarationTest.java

@@ -51,6 +51,15 @@ public class ASTFieldDeclarationTest extends ParserTst {
             " String[] foo;" + PMD.EOL +
             "}";
 
+    @Test
+    public void testWithAnnotation() {
+        ASTCompilationUnit cu = parseJava15(TEST5);
+        ASTFieldDeclaration node = cu.findDescendantsOfType(ASTFieldDeclaration.class).get(0);
+        assertFalse(node.isInterfaceMember());
+        assertTrue(node.isAnnotationMember());
+    }
+
+
     private static final String TEST2 =
             "class Foo {" + PMD.EOL +
             " String[][][] foo;" + PMD.EOL +
@@ -67,6 +76,8 @@ public class ASTFieldDeclarationTest extends ParserTst {
             " private int x;" + PMD.EOL +
             "}";
 
+    private static final String TEST5 = "public @interface Foo {" + PMD.EOL + " int BAR = 6;" + PMD.EOL + "}";
+
     @Test
     public void testGetVariableName() {
         int id = 0;

pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/optimizations/xml/RedundantFieldInitializer.xml

@@ -1309,6 +1309,16 @@ public class SomeClass {
         <code><![CDATA[
 public class SomeClass {
     private float someNumber = 0.1f;
+}
+        ]]></code>
+    </test-code>
+
+    <test-code>
+        <description>#215 - False positive for annotation fields</description>
+        <expected-problems>0</expected-problems>
+        <code><![CDATA[
+public @interface SomeAnnotation {
+    int CONSTANT = 0;
 }
         ]]></code>
     </test-code>