aoqi@0: /*
aoqi@0:  * Copyright (c) 2005, 2012, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.  Oracle designates this
aoqi@0:  * particular file as subject to the "Classpath" exception as provided
aoqi@0:  * by Oracle in the LICENSE file that accompanied this code.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  */
aoqi@0: 
aoqi@0: package com.sun.tools.javac.util;
aoqi@0: 
aoqi@0: import com.sun.tools.javac.code.Type;
aoqi@0: 
aoqi@0: /**
aoqi@0:  * Utilities for operating on constant values.
aoqi@0:  *
aoqi@0:  * <p><b>This is NOT part of any supported API.
aoqi@0:  * If you write code that depends on this, you do so at your own risk.
aoqi@0:  * This code and its internal interfaces are subject to change or
aoqi@0:  * deletion without notice.</b>
aoqi@0:  */
aoqi@0: public class Constants {
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Converts a constant in internal representation (in which
aoqi@0:      * boolean, char, byte, short, and int are each represented by an
aoqi@0:      * Integer) into standard representation.  Other values (including
aoqi@0:      * null) are returned unchanged.
aoqi@0:      */
aoqi@0:     public static Object decode(Object value, Type type) {
aoqi@0:         if (value instanceof Integer) {
aoqi@0:             int i = (Integer) value;
aoqi@0:             switch (type.getTag()) {
aoqi@0:             case BOOLEAN:  return i != 0;
aoqi@0:             case CHAR:     return (char) i;
aoqi@0:             case BYTE:     return (byte) i;
aoqi@0:             case SHORT:    return (short) i;
aoqi@0:             }
aoqi@0:         }
aoqi@0:         return value;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Returns a string representation of a constant value (given in
aoqi@0:      * internal representation), quoted and formatted as in Java source.
aoqi@0:      */
aoqi@0:     public static String format(Object value, Type type) {
aoqi@0:         value = decode(value, type);
aoqi@0:         switch (type.getTag()) {
aoqi@0:         case BYTE:      return formatByte((Byte) value);
aoqi@0:         case LONG:      return formatLong((Long) value);
aoqi@0:         case FLOAT:     return formatFloat((Float) value);
aoqi@0:         case DOUBLE:    return formatDouble((Double) value);
aoqi@0:         case CHAR:      return formatChar((Character) value);
aoqi@0:         }
aoqi@0:         if (value instanceof String)
aoqi@0:             return formatString((String) value);
aoqi@0:         return value + "";
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Returns a string representation of a constant value (given in
aoqi@0:      * standard wrapped representation), quoted and formatted as in
aoqi@0:      * Java source.
aoqi@0:      */
aoqi@0:     public static String format(Object value) {
aoqi@0:         if (value instanceof Byte)      return formatByte((Byte) value);
aoqi@0:         if (value instanceof Short)     return formatShort((Short) value);
aoqi@0:         if (value instanceof Long)      return formatLong((Long) value);
aoqi@0:         if (value instanceof Float)     return formatFloat((Float) value);
aoqi@0:         if (value instanceof Double)    return formatDouble((Double) value);
aoqi@0:         if (value instanceof Character) return formatChar((Character) value);
aoqi@0:         if (value instanceof String)    return formatString((String) value);
aoqi@0:         if (value instanceof Integer ||
aoqi@0:             value instanceof Boolean)   return value.toString();
aoqi@0:         else
aoqi@0:             throw new IllegalArgumentException("Argument is not a primitive type or a string; it " +
aoqi@0:                                                ((value == null) ?
aoqi@0:                                                 "is a null value." :
aoqi@0:                                                 "has class " +
aoqi@0:                                                 value.getClass().getName()) + "." );
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static String formatByte(byte b) {
aoqi@0:         return String.format("(byte)0x%02x", b);
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static String formatShort(short s) {
aoqi@0:         return String.format("(short)%d", s);
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static String formatLong(long lng) {
aoqi@0:         return lng + "L";
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static String formatFloat(float f) {
aoqi@0:         if (Float.isNaN(f))
aoqi@0:             return "0.0f/0.0f";
aoqi@0:         else if (Float.isInfinite(f))
aoqi@0:             return (f < 0) ? "-1.0f/0.0f" : "1.0f/0.0f";
aoqi@0:         else
aoqi@0:             return f + "f";
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static String formatDouble(double d) {
aoqi@0:         if (Double.isNaN(d))
aoqi@0:             return "0.0/0.0";
aoqi@0:         else if (Double.isInfinite(d))
aoqi@0:             return (d < 0) ? "-1.0/0.0" : "1.0/0.0";
aoqi@0:         else
aoqi@0:             return d + "";
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static String formatChar(char c) {
aoqi@0:         return '\'' + Convert.quote(c) + '\'';
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static String formatString(String s) {
aoqi@0:         return '"' + Convert.quote(s) + '"';
aoqi@0:     }
aoqi@0: }