1 /*
   2  * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
   3  */
   4 /*
   5  * Licensed to the Apache Software Foundation (ASF) under one or more
   6  * contributor license agreements.  See the NOTICE file distributed with
   7  * this work for additional information regarding copyright ownership.
   8  * The ASF licenses this file to You under the Apache License, Version 2.0
   9  * (the "License"); you may not use this file except in compliance with
  10  * the License.  You may obtain a copy of the License at
  11  *
  12  *      http://www.apache.org/licenses/LICENSE-2.0
  13  *
  14  * Unless required by applicable law or agreed to in writing, software
  15  * distributed under the License is distributed on an "AS IS" BASIS,
  16  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  17  * See the License for the specific language governing permissions and
  18  * limitations under the License.
  19  */
  20 
  21 package com.sun.org.apache.xalan.internal.xsltc.compiler;
  22 
  23 import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
  24 import com.sun.org.apache.bcel.internal.generic.INVOKESPECIAL;
  25 import com.sun.org.apache.bcel.internal.generic.INVOKEVIRTUAL;
  26 import com.sun.org.apache.bcel.internal.generic.Instruction;
  27 import com.sun.org.apache.bcel.internal.generic.InstructionList;
  28 import com.sun.org.apache.bcel.internal.generic.NEW;
  29 import com.sun.org.apache.bcel.internal.generic.PUSH;
  30 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
  31 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
  32 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
  33 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;
  34 import java.util.List;
  35 
  36 /**
  37  * @author Jacek Ambroziak
  38  * @author Santiago Pericas-Geertsen
  39  * @LastModified: Oct 2017
  40  */
  41 final class ConcatCall extends FunctionCall {
  42     public ConcatCall(QName fname, List<Expression> arguments) {
  43         super(fname, arguments);
  44     }
  45 
  46     public Type typeCheck(SymbolTable stable) throws TypeCheckError {
  47         for (int i = 0; i < argumentCount(); i++) {
  48             final Expression exp = argument(i);
  49             if (!exp.typeCheck(stable).identicalTo(Type.String)) {
  50                 setArgument(i, new CastExpr(exp, Type.String));
  51             }
  52         }
  53         return _type = Type.String;
  54     }
  55 
  56     /** translate leaves a String on the stack */
  57     public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
  58         final ConstantPoolGen cpg = classGen.getConstantPool();
  59         final InstructionList il = methodGen.getInstructionList();
  60         final int nArgs = argumentCount();
  61 
  62         switch (nArgs) {
  63         case 0:
  64             il.append(new PUSH(cpg, EMPTYSTRING));
  65             break;
  66 
  67         case 1:
  68             argument().translate(classGen, methodGen);
  69             break;
  70 
  71         default:
  72             final int initBuffer = cpg.addMethodref(STRING_BUFFER_CLASS,
  73                                                     "<init>", "()V");
  74             final Instruction append =
  75                 new INVOKEVIRTUAL(cpg.addMethodref(STRING_BUFFER_CLASS,
  76                                                    "append",
  77                                                    "("+STRING_SIG+")"
  78                                                    +STRING_BUFFER_SIG));
  79 
  80             final int toString = cpg.addMethodref(STRING_BUFFER_CLASS,
  81                                                   "toString",
  82                                                   "()"+STRING_SIG);
  83 
  84             il.append(new NEW(cpg.addClass(STRING_BUFFER_CLASS)));
  85             il.append(DUP);
  86             il.append(new INVOKESPECIAL(initBuffer));
  87             for (int i = 0; i < nArgs; i++) {
  88                 argument(i).translate(classGen, methodGen);
  89                 il.append(append);
  90             }
  91             il.append(new INVOKEVIRTUAL(toString));
  92         }
  93     }
  94 }