/*
 * Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.
 */
/*
 * 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.
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/*
 * $Id: AttributeValueTemplate.java,v 1.2.4.1 2005/09/01 10:26:57 pvedula Exp $
 */

package com.sun.org.apache.xalan.internal.xsltc.compiler;

import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
import com.sun.org.apache.bcel.internal.generic.INVOKESPECIAL;
import com.sun.org.apache.bcel.internal.generic.INVOKEVIRTUAL;
import com.sun.org.apache.bcel.internal.generic.Instruction;
import com.sun.org.apache.bcel.internal.generic.InstructionList;
import com.sun.org.apache.bcel.internal.generic.NEW;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ErrorMsg;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;
import java.util.Iterator;
import java.util.List;
import java.util.NoSuchElementException;
import java.util.StringTokenizer;

Author:Jacek Ambroziak, Santiago Pericas-Geertsen
@LastModified: Oct 2017
/** * @author Jacek Ambroziak * @author Santiago Pericas-Geertsen * @LastModified: Oct 2017 */
final class AttributeValueTemplate extends AttributeValue { final static int OUT_EXPR = 0; final static int IN_EXPR = 1; final static int IN_EXPR_SQUOTES = 2; final static int IN_EXPR_DQUOTES = 3; final static String DELIMITER = "\uFFFE"; // A Unicode nonchar public AttributeValueTemplate(String value, Parser parser, SyntaxTreeNode parent) { setParent(parent); setParser(parser); try { parseAVTemplate(value, parser); } catch (NoSuchElementException e) { reportError(parent, parser, ErrorMsg.ATTR_VAL_TEMPLATE_ERR, value); } }
Two-pass parsing of ATVs. In the first pass, double curly braces are replaced by one, and expressions are delimited using DELIMITER. The second pass splits up the resulting buffer into literal and non-literal expressions. Errors are reported during the first pass.
/** * Two-pass parsing of ATVs. In the first pass, double curly braces are * replaced by one, and expressions are delimited using DELIMITER. The * second pass splits up the resulting buffer into literal and non-literal * expressions. Errors are reported during the first pass. */
private void parseAVTemplate(String text, Parser parser) { StringTokenizer tokenizer = new StringTokenizer(text, "{}\"\'", true); /* * First pass: replace double curly braces and delimit expressions * Simple automaton to parse ATVs, delimit expressions and report * errors. */ String t = null; String lookahead = null; StringBuilder buffer = new StringBuilder(); int state = OUT_EXPR; while (tokenizer.hasMoreTokens()) { // Use lookahead if available if (lookahead != null) { t = lookahead; lookahead = null; } else { t = tokenizer.nextToken(); } if (t.length() == 1) { switch (t.charAt(0)) { case '{': switch (state) { case OUT_EXPR: lookahead = tokenizer.nextToken(); if (lookahead.equals("{")) { buffer.append(lookahead); // replace {{ by { lookahead = null; } else { buffer.append(DELIMITER); state = IN_EXPR; } break; case IN_EXPR: case IN_EXPR_SQUOTES: case IN_EXPR_DQUOTES: reportError(getParent(), parser, ErrorMsg.ATTR_VAL_TEMPLATE_ERR, text); break; } break; case '}': switch (state) { case OUT_EXPR: lookahead = tokenizer.nextToken(); if (lookahead.equals("}")) { buffer.append(lookahead); // replace }} by } lookahead = null; } else { reportError(getParent(), parser, ErrorMsg.ATTR_VAL_TEMPLATE_ERR, text); } break; case IN_EXPR: buffer.append(DELIMITER); state = OUT_EXPR; break; case IN_EXPR_SQUOTES: case IN_EXPR_DQUOTES: buffer.append(t); break; } break; case '\'': switch (state) { case IN_EXPR: state = IN_EXPR_SQUOTES; break; case IN_EXPR_SQUOTES: state = IN_EXPR; break; case OUT_EXPR: case IN_EXPR_DQUOTES: break; } buffer.append(t); break; case '\"': switch (state) { case IN_EXPR: state = IN_EXPR_DQUOTES; break; case IN_EXPR_DQUOTES: state = IN_EXPR; break; case OUT_EXPR: case IN_EXPR_SQUOTES: break; } buffer.append(t); break; default: buffer.append(t); break; } } else { buffer.append(t); } } // Must be in OUT_EXPR at the end of parsing if (state != OUT_EXPR) { reportError(getParent(), parser, ErrorMsg.ATTR_VAL_TEMPLATE_ERR, text); } /* * Second pass: split up buffer into literal and non-literal expressions. */ tokenizer = new StringTokenizer(buffer.toString(), DELIMITER, true); while (tokenizer.hasMoreTokens()) { t = tokenizer.nextToken(); if (t.equals(DELIMITER)) { addElement(parser.parseExpression(this, tokenizer.nextToken())); tokenizer.nextToken(); // consume other delimiter } else { addElement(new LiteralExpr(t)); } } } public Type typeCheck(SymbolTable stable) throws TypeCheckError { final List<SyntaxTreeNode> contents = getContents(); final int n = contents.size(); for (int i = 0; i < n; i++) { final Expression exp = (Expression)contents.get(i); if (!exp.typeCheck(stable).identicalTo(Type.String)) { contents.set(i, new CastExpr(exp, Type.String)); } } return _type = Type.String; } public String toString() { final StringBuilder buffer = new StringBuilder("AVT:["); final int count = elementCount(); for (int i = 0; i < count; i++) { buffer.append(elementAt(i).toString()); if (i < count - 1) buffer.append(' '); } return buffer.append(']').toString(); } public void translate(ClassGenerator classGen, MethodGenerator methodGen) { if (elementCount() == 1) { final Expression exp = (Expression)elementAt(0); exp.translate(classGen, methodGen); } else { final ConstantPoolGen cpg = classGen.getConstantPool(); final InstructionList il = methodGen.getInstructionList(); final int initBuffer = cpg.addMethodref(STRING_BUFFER_CLASS, "<init>", "()V"); final Instruction append = new INVOKEVIRTUAL(cpg.addMethodref(STRING_BUFFER_CLASS, "append", "(" + STRING_SIG + ")" + STRING_BUFFER_SIG)); final int toString = cpg.addMethodref(STRING_BUFFER_CLASS, "toString", "()"+STRING_SIG); il.append(new NEW(cpg.addClass(STRING_BUFFER_CLASS))); il.append(DUP); il.append(new INVOKESPECIAL(initBuffer)); // StringBuilder is on the stack final Iterator<SyntaxTreeNode> elements = elements(); while (elements.hasNext()) { final Expression exp = (Expression)elements.next(); exp.translate(classGen, methodGen); il.append(append); } il.append(new INVOKEVIRTUAL(toString)); } } }