1 /* 2 * Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved. 3 * @LastModified: Oct 2017 4 */ 5 /* 6 * Licensed to the Apache Software Foundation (ASF) under one or more 7 * contributor license agreements. See the NOTICE file distributed with 8 * this work for additional information regarding copyright ownership. 9 * The ASF licenses this file to You under the Apache License, Version 2.0 10 * (the "License"); you may not use this file except in compliance with 11 * the License. You may obtain a copy of the License at 12 * 13 * http://www.apache.org/licenses/LICENSE-2.0 14 * 15 * Unless required by applicable law or agreed to in writing, software 16 * distributed under the License is distributed on an "AS IS" BASIS, 17 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 18 * See the License for the specific language governing permissions and 19 * limitations under the License. 20 */ 21 22 package com.sun.org.apache.xalan.internal.xsltc.compiler.util; 23 24 import com.sun.org.apache.bcel.internal.generic.Instruction; 25 import com.sun.org.apache.bcel.internal.generic.InstructionList; 26 import com.sun.org.apache.bcel.internal.generic.PUSH; 27 import com.sun.org.apache.xalan.internal.xsltc.compiler.Constants; 28 29 /** 30 * @author Jacek Ambroziak 31 * @author Santiago Pericas-Geertsen 32 */ 33 public final class VoidType extends Type { 34 protected VoidType() {} 35 36 public String toString() { 37 return "void"; 38 } 39 40 public boolean identicalTo(Type other) { 41 return this == other; 42 } 43 44 public String toSignature() { 45 return "V"; 46 } 47 48 public com.sun.org.apache.bcel.internal.generic.Type toJCType() { 49 return null; // should never be called 50 } 51 52 public Instruction POP() { 53 return NOP; 54 } 55 56 /** 57 * Translates a void into an object of internal type <code>type</code>. 58 * This translation is needed when calling external functions 59 * that return void. 60 * 61 * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo 62 */ 63 public void translateTo(ClassGenerator classGen, MethodGenerator methodGen, 64 Type type) { 65 if (type == Type.String) { 66 translateTo(classGen, methodGen, (StringType) type); 67 } 68 else { 69 ErrorMsg err = new ErrorMsg(ErrorMsg.DATA_CONVERSION_ERR, 70 toString(), type.toString()); 71 classGen.getParser().reportError(Constants.FATAL, err); 72 } 73 } 74 75 /** 76 * Translates a void into a string by pushing the empty string ''. 77 * 78 * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo 79 */ 80 public void translateTo(ClassGenerator classGen, MethodGenerator methodGen, 81 StringType type) { 82 final InstructionList il = methodGen.getInstructionList(); 83 il.append(new PUSH(classGen.getConstantPool(), "")); 84 } 85 86 /** 87 * Translates an external (primitive) Java type into a void. 88 * Only an external "void" can be converted to this class. 89 */ 90 public void translateFrom(ClassGenerator classGen, MethodGenerator methodGen, 91 Class<?> clazz) { 92 if (!clazz.getName().equals("void")) { 93 ErrorMsg err = new ErrorMsg(ErrorMsg.DATA_CONVERSION_ERR, 94 toString(), clazz.getName()); 95 classGen.getParser().reportError(Constants.FATAL, err); 96 } 97 } 98 }