Clean up code (#1130)

* Simplify code, add final keyword, use diamond operator, correct English, use lambdas, remove .toString, use .isEmpty(), use .addAll, and more
* Thanks to IntelliJ code analyses feature

Author: jkosternl

src/main/java/com/networknt/org/apache/commons/validator/routines/DomainValidator.java

@@ -96,7 +96,6 @@ public enum ArrayType {
          * @since 1.7
          */
         LOCAL_MINUS
-        ;
     }
 
     private static class IDNBUGHOLDER {

src/main/java/com/networknt/org/apache/commons/validator/routines/EmailValidator.java

@@ -186,11 +186,7 @@ public boolean isValid(final String email) {
             return false;
         }
 
-        if (!isValidDomain(emailMatcher.group(2))) {
-            return false;
-        }
-
-        return true;
+	    return isValidDomain(emailMatcher.group(2));
     }
 
     /**

src/main/java/com/networknt/org/apache/commons/validator/routines/InetAddressValidator.java

@@ -213,9 +213,6 @@ public boolean isValidInet6Address(String inet6Address) {
             }
             validOctets++;
         }
-        if (validOctets > IPV6_MAX_HEX_GROUPS || validOctets < IPV6_MAX_HEX_GROUPS && !containsCompressedZeroes) {
-            return false;
-        }
-        return true;
+	    return validOctets <= IPV6_MAX_HEX_GROUPS && (validOctets >= IPV6_MAX_HEX_GROUPS || containsCompressedZeroes);
     }
 }

src/main/java/com/networknt/schema/AnnotationKeyword.java

@@ -44,7 +44,7 @@ public Set<ValidationMessage> validate(ExecutionContext executionContext, JsonNo
             return Collections.emptySet();
         }
 
-        protected Object getAnnotationValue(JsonNode schemaNode) {
+        private Object getAnnotationValue(JsonNode schemaNode) {
             if (schemaNode.isTextual()) {
                 return schemaNode.textValue(); 
             } else if (schemaNode.isNumber()) {
@@ -62,7 +62,7 @@ public AnnotationKeyword(String keyword) {
 
     @Override
     public JsonValidator newValidator(SchemaLocation schemaLocation, JsonNodePath evaluationPath, JsonNode schemaNode,
-                                      JsonSchema parentSchema, ValidationContext validationContext) throws JsonSchemaException, Exception {
+                                      JsonSchema parentSchema, ValidationContext validationContext) {
         return new Validator(schemaLocation, evaluationPath, schemaNode, parentSchema, validationContext, this);
     }
 }

src/main/java/com/networknt/schema/BaseJsonValidator.java

@@ -147,7 +147,7 @@ public static void debug(Logger logger, ExecutionContext executionContext, JsonN
 
     /**
      * Checks based on the current {@link DiscriminatorContext} whether the provided {@link JsonSchema} a match against
-     * against the current discriminator.
+     * the current discriminator.
      *
      * @param currentDiscriminatorContext the currently active {@link DiscriminatorContext}
      * @param discriminator               the discriminator to use for the check

src/main/java/com/networknt/schema/Collector.java

@@ -32,15 +32,15 @@ public interface Collector<E> {
      * at multiple touch points or accumulating data at same touch point.
 	 * @param object Object
      */
-    public void combine(Object object);
+    void combine(Object object);
 
     /**
      * Final method called by the framework that returns the actual collected data.
      * If the collector is not accumulating data or being used to collect data at
      * multiple touch points, only this method can be implemented.
 	 * @return E element
      */
-    public E collect();
+    E collect();
 
 
 }

src/main/java/com/networknt/schema/DefaultJsonMetaSchemaFactory.java

@@ -15,6 +15,7 @@
  */
 package com.networknt.schema;
 
+import java.util.Map;
 import java.util.Map.Entry;
 
 import com.fasterxml.jackson.databind.JsonNode;
@@ -60,7 +61,7 @@ protected JsonMetaSchema.Builder loadMetaSchemaBuilder(String iri, JsonSchemaFac
                 // Process vocabularies
                 JsonNode vocabulary = schema.getSchemaNode().get("$vocabulary");
                 if (vocabulary != null) {
-                    builder.vocabularies(vocabularies -> vocabularies.clear());
+                    builder.vocabularies(Map::clear);
                     for (Entry<String, JsonNode> vocabs : vocabulary.properties()) {
                         builder.vocabulary(vocabs.getKey(), vocabs.getValue().booleanValue());
                     }
@@ -71,7 +72,7 @@ protected JsonMetaSchema.Builder loadMetaSchemaBuilder(String iri, JsonSchemaFac
     }
 
     private static class Holder {
-        private static DefaultJsonMetaSchemaFactory INSTANCE = new DefaultJsonMetaSchemaFactory();
+        private static final DefaultJsonMetaSchemaFactory INSTANCE = new DefaultJsonMetaSchemaFactory();
     }
 
     public static DefaultJsonMetaSchemaFactory getInstance() {

src/main/java/com/networknt/schema/DependenciesValidator.java

@@ -27,8 +27,8 @@
  */
 public class DependenciesValidator extends BaseJsonValidator implements JsonValidator {
     private static final Logger logger = LoggerFactory.getLogger(DependenciesValidator.class);
-    private final Map<String, List<String>> propertyDeps = new HashMap<String, List<String>>();
-    private final Map<String, JsonSchema> schemaDeps = new HashMap<String, JsonSchema>();
+    private final Map<String, List<String>> propertyDeps = new HashMap<>();
+    private final Map<String, JsonSchema> schemaDeps = new HashMap<>();
 
     /**
      * Constructor.

src/main/java/com/networknt/schema/DependentRequired.java

@@ -27,7 +27,7 @@
  */
 public class DependentRequired extends BaseJsonValidator implements JsonValidator {
     private static final Logger logger = LoggerFactory.getLogger(DependentRequired.class);
-    private final Map<String, List<String>> propertyDependencies = new HashMap<String, List<String>>();
+    private final Map<String, List<String>> propertyDependencies = new HashMap<>();
 
     public DependentRequired(SchemaLocation schemaLocation, JsonNodePath evaluationPath, JsonNode schemaNode, JsonSchema parentSchema, ValidationContext validationContext) {
 
@@ -49,7 +49,7 @@ public DependentRequired(SchemaLocation schemaLocation, JsonNodePath evaluationP
     public Set<ValidationMessage> validate(ExecutionContext executionContext, JsonNode node, JsonNode rootNode, JsonNodePath instanceLocation) {
         debug(logger, executionContext, node, rootNode, instanceLocation);
 
-        Set<ValidationMessage> errors = new LinkedHashSet<ValidationMessage>();
+        Set<ValidationMessage> errors = new LinkedHashSet<>();
 
         for (Iterator<String> it = node.fieldNames(); it.hasNext(); ) {
             String pname = it.next();

src/main/java/com/networknt/schema/DisallowUnknownJsonMetaSchemaFactory.java

@@ -28,7 +28,7 @@ public JsonMetaSchema getMetaSchema(String iri, JsonSchemaFactory schemaFactory,
     }
 
     private static class Holder {
-        private static DisallowUnknownJsonMetaSchemaFactory INSTANCE = new DisallowUnknownJsonMetaSchemaFactory();
+        private static final DisallowUnknownJsonMetaSchemaFactory INSTANCE = new DisallowUnknownJsonMetaSchemaFactory();
     }
 
     /**