[java] Push isStatic() down to declaration

Only on ASTMethodDeclaration, ASTFieldDeclaration and ASTAnyTypeDeclaration.
This makes it possible to remove it
from AccessNode.

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

@@ -135,6 +135,14 @@ public interface ASTAnyTypeDeclaration
         return hasModifiers(ABSTRACT);
     }
 
+    /**
+     * Returns true if this type is static. Only inner types can be static.
+     */
+    @Override
+    default boolean isStatic() {
+        return hasModifiers(JModifier.STATIC);
+    }
+
 
     /**
      * Returns the enum constants declared by this enum. If this is not

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

@@ -73,4 +73,11 @@ public final class ASTFieldDeclaration extends AbstractJavaNode
         return getFirstChildOfType(ASTType.class);
     }
 
+    /**
+     * Returns true if this field is static.
+     */
+    @Override
+    public boolean isStatic() {
+        return hasModifiers(JModifier.STATIC);
+    }
 }

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

@@ -132,6 +132,12 @@ public final class ASTMethodDeclaration extends AbstractMethodOrConstructorDecla
         return getResultTypeNode().isVoid();
     }
 
+    /** Returns true if this method is static. */
+    @Override
+    public boolean isStatic() {
+        return hasModifiers(JModifier.STATIC);
+    }
+
 
     /**
      * Returns the default clause, if this is an annotation method declaration

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

@@ -16,7 +16,8 @@ import net.sourceforge.pmd.lang.ast.NodeStream;
  * A node that owns a {@linkplain ASTModifierList modifier list}.
  *
  * <p>{@link AccessNode} methods take into account the syntactic context of the
- * declaration, e.g. {@link #isPublic()} will always return true for a field
+ * declaration, e.g. {@link #hasModifiers(JModifier, JModifier...) hasModifiers(JModifier.PUBLIC)}
+ * will always return true for a field
  * declared inside an interface, regardless of whether the {@code public}
  * modifier was specified explicitly or not. If you want to know whether
  * the modifier was explicitly stated, use {@link #hasExplicitModifiers(JModifier, JModifier...)}.

pmd-java/src/main/java/net/sourceforge/pmd/lang/java/rule/codestyle/AtLeastOneConstructorRule.java

@@ -12,6 +12,7 @@ import net.sourceforge.pmd.lang.java.ast.ASTAnyTypeDeclaration;
 import net.sourceforge.pmd.lang.java.ast.ASTClassOrInterfaceDeclaration;
 import net.sourceforge.pmd.lang.java.ast.ASTConstructorDeclaration;
 import net.sourceforge.pmd.lang.java.ast.AccessNode;
+import net.sourceforge.pmd.lang.java.ast.JModifier;
 import net.sourceforge.pmd.lang.java.rule.AbstractIgnoredAnnotationRule;
 import net.sourceforge.pmd.lang.java.rule.design.UseUtilityClassRule;
 
@@ -50,7 +51,7 @@ public class AtLeastOneConstructorRule extends AbstractIgnoredAnnotationRule {
         NodeStream<AccessNode> members = node.getDeclarations()
                                              .filterIs(AccessNode.class)
                                              .filterNot(it -> it instanceof ASTAnyTypeDeclaration);
-        if (members.isEmpty() || members.any(it -> !it.isStatic())) {
+        if (members.isEmpty() || members.any(it -> !it.hasModifiers(JModifier.STATIC))) {
             // Do we have any non-static members?
             addViolation(data, node);
         }