001: /* ====================================================================
002: * Tea - Copyright (c) 1997-2000 Walt Disney Internet Group
003: * ====================================================================
004: * The Tea Software License, Version 1.1
005: *
006: * Copyright (c) 2000 Walt Disney Internet Group. All rights reserved.
007: *
008: * Redistribution and use in source and binary forms, with or without
009: * modification, are permitted provided that the following conditions
010: * are met:
011: *
012: * 1. Redistributions of source code must retain the above copyright
013: * notice, this list of conditions and the following disclaimer.
014: *
015: * 2. Redistributions in binary form must reproduce the above copyright
016: * notice, this list of conditions and the following disclaimer in
017: * the documentation and/or other materials provided with the
018: * distribution.
019: *
020: * 3. The end-user documentation included with the redistribution,
021: * if any, must include the following acknowledgment:
022: * "This product includes software developed by the
023: * Walt Disney Internet Group (http://opensource.go.com/)."
024: * Alternately, this acknowledgment may appear in the software itself,
025: * if and wherever such third-party acknowledgments normally appear.
026: *
027: * 4. The names "Tea", "TeaServlet", "Kettle", "Trove" and "BeanDoc" must
028: * not be used to endorse or promote products derived from this
029: * software without prior written permission. For written
030: * permission, please contact opensource@dig.com.
031: *
032: * 5. Products derived from this software may not be called "Tea",
033: * "TeaServlet", "Kettle" or "Trove", nor may "Tea", "TeaServlet",
034: * "Kettle", "Trove" or "BeanDoc" appear in their name, without prior
035: * written permission of the Walt Disney Internet Group.
036: *
037: * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
038: * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
039: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
040: * DISCLAIMED. IN NO EVENT SHALL THE WALT DISNEY INTERNET GROUP OR ITS
041: * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
042: * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
043: * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
044: * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
045: * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
046: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
047: * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
048: * ====================================================================
049: *
050: * For more information about Tea, please see http://opensource.go.com/.
051: */
052:
053: package com.go.tea.parsetree;
054:
055: import com.go.tea.compiler.SourceInfo;
056: import com.go.tea.compiler.Token;
057: import java.lang.reflect.Method;
058:
059: /******************************************************************************
060: * An ArrayLookup can access indexed properties on objects. A Bean
061: * Introspector can be used to get the available indexed properties from
062: * an object, however, the only ones supported by Tea are unnamed.
063: * For this reason, the Introspector is not used. Any class with methods named
064: * "get" that return something and have a single parameter (the type of which
065: * is not limited to ints) will support an array lookup.
066: *
067: * <p>Arrays, Collections and Strings are treated specially, and they all
068: * support array lookup on an int typed index.
069: *
070: * @author Brian S O'Neill
071: * @version
072: * <!--$$Revision:--> 23 <!-- $-->, <!--$$JustDate:--> 9/07/00 <!-- $-->
073: * @see com.go.tea.util.BeanAnalyzer
074: */
075: public class ArrayLookup extends Expression {
076: private Expression mExpr;
077: private Token mToken;
078: private Expression mLookupIndex;
079: private Method mMethod;
080:
081: public ArrayLookup(SourceInfo info, Expression expr,
082: Token lookupToken, Expression lookupIndex) {
083: super (info);
084:
085: mExpr = expr;
086: mToken = lookupToken;
087: mLookupIndex = lookupIndex;
088: }
089:
090: public Object accept(NodeVisitor visitor) {
091: return visitor.visit(this );
092: }
093:
094: public Object clone() {
095: ArrayLookup al = (ArrayLookup) super .clone();
096: al.mExpr = (Expression) mExpr.clone();
097: al.mLookupIndex = (Expression) mLookupIndex.clone();
098: return al;
099: }
100:
101: public boolean isExceptionPossible() {
102: // ArrayIndexOutOfBoundsException is always a possibility.
103: return true;
104: }
105:
106: public Expression getExpression() {
107: return mExpr;
108: }
109:
110: public Token getLookupToken() {
111: return mToken;
112: }
113:
114: public Expression getLookupIndex() {
115: return mLookupIndex;
116: }
117:
118: /**
119: * Returns the method to invoke in order to perform the lookup. This is
120: * filled in by the type checker. If the expression type is an array, the
121: * read method is null. A code generator must still be able to get
122: * elements from an array.
123: */
124: public Method getReadMethod() {
125: return mMethod;
126: }
127:
128: public void setExpression(Expression expr) {
129: mExpr = expr;
130: }
131:
132: public void setLookupIndex(Expression lookupIndex) {
133: mLookupIndex = lookupIndex;
134: }
135:
136: public void setReadMethod(Method m) {
137: mMethod = m;
138: }
139: }
|