add fields().that().are[Not]{Static,Final} syntax

Signed-off-by: Manfred Hanke <Manfred.Hanke@tngtech.com>

archunit/src/main/java/com/tngtech/archunit/lang/syntax/MembersThatInternal.java

@@ -111,6 +111,26 @@ public CONJUNCTION areNotPrivate() {
         return givenWith(SyntaxPredicates.areNotPrivate());
     }
 
+    // only applicable to fields and methods; therefore not exposed via MembersThat
+    public CONJUNCTION areStatic() {
+        return givenWith(SyntaxPredicates.areStatic());
+    }
+
+    // only applicable to fields and methods; therefore not exposed via MembersThat
+    public CONJUNCTION areNotStatic() {
+        return givenWith(SyntaxPredicates.areNotStatic());
+    }
+
+    // only applicable to (classes,) fields and methods; therefore not exposed via MembersThat
+    public CONJUNCTION areFinal() {
+        return givenWith(SyntaxPredicates.areFinal());
+    }
+
+    // only applicable to (classes,) fields and methods; therefore not exposed via MembersThat
+    public CONJUNCTION areNotFinal() {
+        return givenWith(SyntaxPredicates.areNotFinal());
+    }
+
     @Override
     public CONJUNCTION haveModifier(JavaModifier modifier) {
         return givenWith(SyntaxPredicates.haveModifier(modifier));

archunit/src/main/java/com/tngtech/archunit/lang/syntax/SyntaxPredicates.java

@@ -28,9 +28,11 @@
 import static com.tngtech.archunit.core.domain.JavaClass.Predicates.simpleNameContaining;
 import static com.tngtech.archunit.core.domain.JavaClass.Predicates.simpleNameEndingWith;
 import static com.tngtech.archunit.core.domain.JavaClass.Predicates.simpleNameStartingWith;
+import static com.tngtech.archunit.core.domain.JavaModifier.FINAL;
 import static com.tngtech.archunit.core.domain.JavaModifier.PRIVATE;
 import static com.tngtech.archunit.core.domain.JavaModifier.PROTECTED;
 import static com.tngtech.archunit.core.domain.JavaModifier.PUBLIC;
+import static com.tngtech.archunit.core.domain.JavaModifier.STATIC;
 import static com.tngtech.archunit.core.domain.properties.HasModifiers.Predicates.modifier;
 import static com.tngtech.archunit.core.domain.properties.HasName.Predicates.nameMatching;
 import static com.tngtech.archunit.lang.conditions.ArchConditions.fullyQualifiedName;
@@ -85,6 +87,22 @@ static DescribedPredicate<HasModifiers> areNotPrivate() {
         return not(modifier(PRIVATE)).as("are not private");
     }
 
+    static DescribedPredicate<HasModifiers> areStatic() {
+        return modifier(STATIC).as("are static");
+    }
+
+    static DescribedPredicate<HasModifiers> areNotStatic() {
+        return not(modifier(STATIC)).as("are not static");
+    }
+
+    static DescribedPredicate<HasModifiers> areFinal() {
+        return modifier(FINAL).as("are final");
+    }
+
+    static DescribedPredicate<HasModifiers> areNotFinal() {
+        return not(modifier(FINAL)).as("are not final");
+    }
+
     static DescribedPredicate<HasName> haveFullyQualifiedName(String name) {
         return have(fullyQualifiedName(name));
     }

archunit/src/main/java/com/tngtech/archunit/lang/syntax/elements/FieldsThat.java

@@ -137,4 +137,36 @@ public interface FieldsThat<CONJUNCTION extends GivenFieldsConjunction> extends
      */
     @PublicAPI(usage = ACCESS)
     CONJUNCTION doNotHaveRawType(DescribedPredicate<? super JavaClass> predicate);
+
+    /**
+     * Matches static fields.
+     *
+     * @return A syntax conjunction element, which can be completed to form a full rule
+     */
+    @PublicAPI(usage = ACCESS)
+    CONJUNCTION areStatic();
+
+    /**
+     * Matches non-static fields.
+     *
+     * @return A syntax conjunction element, which can be completed to form a full rule
+     */
+    @PublicAPI(usage = ACCESS)
+    CONJUNCTION areNotStatic();
+
+    /**
+     * Matches final fields.
+     *
+     * @return A syntax conjunction element, which can be completed to form a full rule
+     */
+    @PublicAPI(usage = ACCESS)
+    CONJUNCTION areFinal();
+
+    /**
+     * Matches non-final fields.
+     *
+     * @return A syntax conjunction element, which can be completed to form a full rule
+     */
+    @PublicAPI(usage = ACCESS)
+    CONJUNCTION areNotFinal();
 }

archunit/src/test/java/com/tngtech/archunit/lang/syntax/elements/GivenFieldsTest.java

@@ -55,7 +55,14 @@ public static Object[][] restricted_property_rule_starts() {
 
                 $(described(fields().that().doNotHaveRawType(String.class)), allFieldsExcept(FIELD_A)),
                 $(described(fields().that().doNotHaveRawType(String.class.getName())), allFieldsExcept(FIELD_A)),
-                $(described(fields().that().doNotHaveRawType(equivalentTo(String.class))), allFieldsExcept(FIELD_A))
+                $(described(fields().that().doNotHaveRawType(equivalentTo(String.class))), allFieldsExcept(FIELD_A)),
+
+                $(described(fields().that().areFinal()), ImmutableSet.of(FIELD_A, FIELD_B)),
+                $(described(fields().that().areNotFinal()), ImmutableSet.of(FIELD_C, FIELD_D)),
+                $(described(fields().that().areStatic()), ImmutableSet.of(FIELD_B, FIELD_D)),
+                $(described(fields().that().areNotStatic()), ImmutableSet.of(FIELD_A, FIELD_C)),
+
+                $(described(fields().that().areStatic().and().areFinal()), ImmutableSet.of(FIELD_B))
         );
     }
 
@@ -80,11 +87,11 @@ private static Set<String> allFieldsExcept(String... fieldNames) {
 
     @SuppressWarnings({"unused"})
     private static class ClassWithVariousMembers {
-        private String fieldA;
+        private final String fieldA = "A";
         @A
-        protected Object fieldB;
+        protected static final Object fieldB = 'B';
         public List<?> fieldC;
-        Map<?, ?> fieldD;
+        static Map<?, ?> fieldD;
     }
 
     private @interface A {