1 /* 2 * Copyright 2016 Federico Tomassetti 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.github.javaparser.symbolsolver.model.typesystem; 18 19 import com.github.javaparser.resolution.types.ResolvedType; 20 21 /** 22 * This is a virtual type used to represent null values. 23 * 24 * @author Federico Tomassetti 25 */ 26 public class NullType implements ResolvedType { 27 28 public static final NullType INSTANCE = new NullType(); 29 30 private NullType() { 31 // prevent instantiation 32 } 33 34 @Override 35 public boolean isArray() { 36 return false; 37 } 38 39 @Override 40 public boolean isPrimitive() { 41 return false; 42 } 43 44 public boolean isNull() { 45 return true; 46 } 47 48 @Override 49 public boolean isReferenceType() { 50 return false; 51 } 52 53 @Override 54 public String describe() { 55 return "null"; 56 } 57 58 @Override 59 public boolean isTypeVariable() { 60 return false; 61 } 62 63 @Override 64 public boolean isAssignableBy(ResolvedType other) { 65 throw new UnsupportedOperationException("It does not make sense to assign a value to null, it can only be assigned"); 66 } 67 68 } 69
