1 /*
   2  * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package com.sun.codemodel.internal;
  27 
  28 
  29 /**
  30  * JClass for generating expressions containing operators
  31  */
  32 
  33 abstract public class JOp {
  34 
  35     private JOp() {
  36     }
  37 
  38 
  39     /**
  40      * Determine whether the top level of an expression involves an
  41      * operator.
  42      */
  43     static boolean hasTopOp(JExpression e) {
  44         return (e instanceof UnaryOp) || (e instanceof BinaryOp);
  45     }
  46 
  47     /* -- Unary operators -- */
  48 
  49     static private class UnaryOp extends JExpressionImpl {
  50 
  51         protected String op;
  52         protected JExpression e;
  53         protected boolean opFirst = true;
  54 
  55         UnaryOp(String op, JExpression e) {
  56             this.op = op;
  57             this.e = e;
  58         }
  59 
  60         UnaryOp(JExpression e, String op) {
  61             this.op = op;
  62             this.e = e;
  63             opFirst = false;
  64         }
  65 
  66         public void generate(JFormatter f) {
  67             if (opFirst)
  68                 f.p('(').p(op).g(e).p(')');
  69             else
  70                 f.p('(').g(e).p(op).p(')');
  71         }
  72 
  73     }
  74 
  75     public static JExpression minus(JExpression e) {
  76         return new UnaryOp("-", e);
  77     }
  78 
  79     /**
  80      * Logical not <tt>'!x'</tt>.
  81      */
  82     public static JExpression not(JExpression e) {
  83         if (e == JExpr.TRUE) return JExpr.FALSE;
  84         if (e == JExpr.FALSE) return JExpr.TRUE;
  85         return new UnaryOp("!", e);
  86     }
  87 
  88     public static JExpression complement(JExpression e) {
  89         return new UnaryOp("~", e);
  90     }
  91 
  92     static private class TightUnaryOp extends UnaryOp {
  93 
  94         TightUnaryOp(JExpression e, String op) {
  95             super(e, op);
  96         }
  97 
  98         public void generate(JFormatter f) {
  99             if (opFirst)
 100                 f.p(op).g(e);
 101             else
 102                 f.g(e).p(op);
 103         }
 104 
 105     }
 106 
 107     public static JExpression incr(JExpression e) {
 108         return new TightUnaryOp(e, "++");
 109     }
 110 
 111     public static JExpression decr(JExpression e) {
 112         return new TightUnaryOp(e, "--");
 113     }
 114 
 115 
 116     /* -- Binary operators -- */
 117 
 118     static private class BinaryOp extends JExpressionImpl {
 119 
 120         String op;
 121         JExpression left;
 122         JGenerable right;
 123 
 124         BinaryOp(String op, JExpression left, JGenerable right) {
 125             this.left = left;
 126             this.op = op;
 127             this.right = right;
 128         }
 129 
 130         public void generate(JFormatter f) {
 131             f.p('(').g(left).p(op).g(right).p(')');
 132         }
 133 
 134     }
 135 
 136     public static JExpression plus(JExpression left, JExpression right) {
 137         return new BinaryOp("+", left, right);
 138     }
 139 
 140     public static JExpression minus(JExpression left, JExpression right) {
 141         return new BinaryOp("-", left, right);
 142     }
 143 
 144     public static JExpression mul(JExpression left, JExpression right) {
 145         return new BinaryOp("*", left, right);
 146     }
 147 
 148     public static JExpression div(JExpression left, JExpression right) {
 149         return new BinaryOp("/", left, right);
 150     }
 151 
 152     public static JExpression mod(JExpression left, JExpression right) {
 153         return new BinaryOp("%", left, right);
 154     }
 155 
 156     public static JExpression shl(JExpression left, JExpression right) {
 157         return new BinaryOp("<<", left, right);
 158     }
 159 
 160     public static JExpression shr(JExpression left, JExpression right) {
 161         return new BinaryOp(">>", left, right);
 162     }
 163 
 164     public static JExpression shrz(JExpression left, JExpression right) {
 165         return new BinaryOp(">>>", left, right);
 166     }
 167 
 168     public static JExpression band(JExpression left, JExpression right) {
 169         return new BinaryOp("&", left, right);
 170     }
 171 
 172     public static JExpression bor(JExpression left, JExpression right) {
 173         return new BinaryOp("|", left, right);
 174     }
 175 
 176     public static JExpression cand(JExpression left, JExpression right) {
 177         if (left == JExpr.TRUE) return right;
 178         if (right == JExpr.TRUE) return left;
 179         if (left == JExpr.FALSE) return left;    // JExpr.FALSE
 180         if (right == JExpr.FALSE) return right;   // JExpr.FALSE
 181         return new BinaryOp("&&", left, right);
 182     }
 183 
 184     public static JExpression cor(JExpression left, JExpression right) {
 185         if (left == JExpr.TRUE) return left;    // JExpr.TRUE
 186         if (right == JExpr.TRUE) return right;   // JExpr.FALSE
 187         if (left == JExpr.FALSE) return right;
 188         if (right == JExpr.FALSE) return left;
 189         return new BinaryOp("||", left, right);
 190     }
 191 
 192     public static JExpression xor(JExpression left, JExpression right) {
 193         return new BinaryOp("^", left, right);
 194     }
 195 
 196     public static JExpression lt(JExpression left, JExpression right) {
 197         return new BinaryOp("<", left, right);
 198     }
 199 
 200     public static JExpression lte(JExpression left, JExpression right) {
 201         return new BinaryOp("<=", left, right);
 202     }
 203 
 204     public static JExpression gt(JExpression left, JExpression right) {
 205         return new BinaryOp(">", left, right);
 206     }
 207 
 208     public static JExpression gte(JExpression left, JExpression right) {
 209         return new BinaryOp(">=", left, right);
 210     }
 211 
 212     public static JExpression eq(JExpression left, JExpression right) {
 213         return new BinaryOp("==", left, right);
 214     }
 215 
 216     public static JExpression ne(JExpression left, JExpression right) {
 217         return new BinaryOp("!=", left, right);
 218     }
 219 
 220     public static JExpression _instanceof(JExpression left, JType right) {
 221         return new BinaryOp("instanceof", left, right);
 222     }
 223 
 224     /* -- Ternary operators -- */
 225 
 226     static private class TernaryOp extends JExpressionImpl {
 227 
 228         String op1;
 229         String op2;
 230         JExpression e1;
 231         JExpression e2;
 232         JExpression e3;
 233 
 234         TernaryOp(String op1, String op2,
 235                   JExpression e1, JExpression e2, JExpression e3) {
 236             this.e1 = e1;
 237             this.op1 = op1;
 238             this.e2 = e2;
 239             this.op2 = op2;
 240             this.e3 = e3;
 241         }
 242 
 243         public void generate(JFormatter f) {
 244             f.p('(').g(e1).p(op1).g(e2).p(op2).g(e3).p(')');
 245         }
 246 
 247     }
 248 
 249     public static JExpression cond(JExpression cond,
 250                                    JExpression ifTrue, JExpression ifFalse) {
 251         return new TernaryOp("?", ":", cond, ifTrue, ifFalse);
 252     }
 253 
 254 }