duke@1: /*
ohair@554:  * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.
duke@1:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@1:  *
duke@1:  * This code is free software; you can redistribute it and/or modify it
duke@1:  * under the terms of the GNU General Public License version 2 only, as
ohair@554:  * published by the Free Software Foundation.  Oracle designates this
duke@1:  * particular file as subject to the "Classpath" exception as provided
ohair@554:  * by Oracle in the LICENSE file that accompanied this code.
duke@1:  *
duke@1:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@1:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@1:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@1:  * version 2 for more details (a copy is included in the LICENSE file that
duke@1:  * accompanied this code).
duke@1:  *
duke@1:  * You should have received a copy of the GNU General Public License version
duke@1:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@1:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@1:  *
ohair@554:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
ohair@554:  * or visit www.oracle.com if you need additional information or have any
ohair@554:  * questions.
duke@1:  */
duke@1: 
duke@1: package com.sun.tools.javac.util;
duke@1: 
duke@1: import com.sun.tools.javac.code.Type;
duke@1: 
duke@1: import static com.sun.tools.javac.code.TypeTags.*;
duke@1: 
duke@1: /**
duke@1:  * Utilities for operating on constant values.
duke@1:  *
jjg@581:  * <p><b>This is NOT part of any supported API.
jjg@581:  * If you write code that depends on this, you do so at your own risk.
duke@1:  * This code and its internal interfaces are subject to change or
duke@1:  * deletion without notice.</b>
duke@1:  */
duke@1: public class Constants {
duke@1: 
duke@1:     /**
duke@1:      * Converts a constant in internal representation (in which
duke@1:      * boolean, char, byte, short, and int are each represented by an
duke@1:      * Integer) into standard representation.  Other values (including
duke@1:      * null) are returned unchanged.
duke@1:      */
duke@1:     public static Object decode(Object value, Type type) {
duke@1:         if (value instanceof Integer) {
duke@1:             int i = (Integer) value;
duke@1:             switch (type.tag) {
duke@1:             case BOOLEAN:  return i != 0;
duke@1:             case CHAR:     return (char) i;
duke@1:             case BYTE:     return (byte) i;
duke@1:             case SHORT:    return (short) i;
duke@1:             }
duke@1:         }
duke@1:         return value;
duke@1:     }
duke@1: 
duke@1:     /**
duke@1:      * Returns a string representation of a constant value (given in
duke@1:      * internal representation), quoted and formatted as in Java source.
duke@1:      */
duke@1:     public static String format(Object value, Type type) {
duke@1:         value = decode(value, type);
duke@1:         switch (type.tag) {
duke@1:         case BYTE:      return formatByte((Byte) value);
duke@1:         case LONG:      return formatLong((Long) value);
duke@1:         case FLOAT:     return formatFloat((Float) value);
duke@1:         case DOUBLE:    return formatDouble((Double) value);
duke@1:         case CHAR:      return formatChar((Character) value);
duke@1:         }
duke@1:         if (value instanceof String)
duke@1:             return formatString((String) value);
duke@1:         return value + "";
duke@1:     }
duke@1: 
duke@1:     /**
duke@1:      * Returns a string representation of a constant value (given in
duke@1:      * standard wrapped representation), quoted and formatted as in
duke@1:      * Java source.
duke@1:      */
duke@1:     public static String format(Object value) {
duke@1:         if (value instanceof Byte)      return formatByte((Byte) value);
darcy@414:         if (value instanceof Short)     return formatShort((Short) value);
duke@1:         if (value instanceof Long)      return formatLong((Long) value);
duke@1:         if (value instanceof Float)     return formatFloat((Float) value);
duke@1:         if (value instanceof Double)    return formatDouble((Double) value);
duke@1:         if (value instanceof Character) return formatChar((Character) value);
duke@1:         if (value instanceof String)    return formatString((String) value);
darcy@414:         if (value instanceof Integer ||
darcy@414:             value instanceof Boolean)   return value.toString();
darcy@414:         else
darcy@414:             throw new IllegalArgumentException("Argument is not a primitive type or a string; it " +
darcy@414:                                                ((value == null) ?
darcy@414:                                                 "is a null value." :
darcy@414:                                                 "has class " +
darcy@414:                                                 value.getClass().getName()) + "." );
duke@1:     }
duke@1: 
duke@1:     private static String formatByte(byte b) {
darcy@414:         return String.format("(byte)0x%02x", b);
darcy@414:     }
darcy@414: 
darcy@414:     private static String formatShort(short s) {
darcy@414:         return String.format("(short)%d", s);
duke@1:     }
duke@1: 
duke@1:     private static String formatLong(long lng) {
duke@1:         return lng + "L";
duke@1:     }
duke@1: 
duke@1:     private static String formatFloat(float f) {
duke@1:         if (Float.isNaN(f))
duke@1:             return "0.0f/0.0f";
duke@1:         else if (Float.isInfinite(f))
duke@1:             return (f < 0) ? "-1.0f/0.0f" : "1.0f/0.0f";
duke@1:         else
duke@1:             return f + "f";
duke@1:     }
duke@1: 
duke@1:     private static String formatDouble(double d) {
duke@1:         if (Double.isNaN(d))
duke@1:             return "0.0/0.0";
duke@1:         else if (Double.isInfinite(d))
duke@1:             return (d < 0) ? "-1.0/0.0" : "1.0/0.0";
duke@1:         else
duke@1:             return d + "";
duke@1:     }
duke@1: 
duke@1:     private static String formatChar(char c) {
duke@1:         return '\'' + Convert.quote(c) + '\'';
duke@1:     }
duke@1: 
duke@1:     private static String formatString(String s) {
duke@1:         return '"' + Convert.quote(s) + '"';
duke@1:     }
duke@1: }