/*

  * Licensed to the Apache Software Foundation (ASF) under one

  * or more contributor license agreements. See the NOTICE file

  * distributed with this work for additional information

  * regarding copyright ownership. The ASF licenses this file

  * to you under the Apache License, Version 2.0 (the

  * "License"); you may not use this file except in compliance

  * with the License. You may obtain a copy of the License at

  *

  * http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing,

  * software distributed under the License is distributed on an

  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

  * KIND, either express or implied. See the License for the

  * specific language governing permissions and limitations

  * under the License.

  */

 package org.apache.johnzon.core;

 import javax.json.JsonString;

 final class JsonStringImpl implements JsonString {

     private final String value;

     private String escape;

     private Integer hashCode = null;

     JsonStringImpl(final String value) {

         if(value == null) {

             throw new NullPointerException("value must not be null");

         }

         this.value = value;

     }

     @Override

     public String getString() {

         return value;

     }

     @Override

     public CharSequence getChars() {

         return value;

     }

     @Override

     public ValueType getValueType() {

         return ValueType.STRING;

     }

     @Override

     public String toString() {

         String s = escape;

         if (s == null) {

             s =  JsonChars.QUOTE_CHAR+Strings.escape(value)+JsonChars.QUOTE_CHAR;

             escape=s;

         }

         return s;

     }

     @Override

     public int hashCode() {

         Integer h = hashCode;

         if (h == null) {

             h = value.hashCode();

             hashCode=h;

         }

         return h;

     }

     @Override

     public boolean equals(final Object obj) {

         return JsonString.class.isInstance(obj) && JsonString.class.cast(obj).getString().equals(value);

     }

 }