convert.java

GJC（Generic Java Compiler）编译器

/**
 * @(#)Convert.java	1.12 03/01/23
 *
 * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
package com.sun.tools.javac.v8.util;

/**
 * Utility class for static conversion methods between numbers
 *  and strings in various formats.
 */
public class Convert {

    public Convert() {
        super();
    }

    /**
      * Convert string to integer.
      */
    public static int string2int(String s, int radix) throws NumberFormatException {
        if (radix == 10) {
            return Integer.parseInt(s, radix);
        } else {
            char[] cs = s.toCharArray();
            int limit = Integer.MAX_VALUE / (radix / 2);
            int n = 0;
            for (int i = 0; i < cs.length; i++) {
                int d = Character.digit(cs[i], radix);
                if (n < 0 || n > limit || n * radix > Integer.MAX_VALUE - d)
                    throw new NumberFormatException();
                n = n * radix + d;
            }
            return n;
        }
    }

    /**
      * Convert string to long integer.
      */
    public static long string2long(String s, int radix) throws NumberFormatException {
        if (radix == 10) {
            return Long.parseLong(s, radix);
        } else {
            char[] cs = s.toCharArray();
            long limit = Long.MAX_VALUE / (radix / 2);
            long n = 0;
            for (int i = 0; i < cs.length; i++) {
                int d = Character.digit(cs[i], radix);
                if (n < 0 || n > limit || n * radix > Long.MAX_VALUE - d)
                    throw new NumberFormatException();
                n = n * radix + d;
            }
            return n;
        }
    }

    /**
      * Convert `len' bytes from utf8 to characters.
      *  Parameters are as in System.arraycopy
      *  Return first index in `dst' past the last copied char.
      *  @param src        The array holding the bytes to convert.
      *  @param sindex     The start index from which bytes are converted.
      *  @param dst        The array holding the converted characters..
      *  @param sindex     The start index from which converted characters
      *                    are written.
      *  @param len        The maximum number of bytes to convert.
      */
    public static int utf2chars(byte[] src, int sindex, char[] dst, int dindex,
            int len) {
        int i = sindex;
        int j = dindex;
        int limit = sindex + len;
        while (i < limit) {
            int b = src[i++] & 255;
            if (b >= 224) {
                b = (b & 15)<< 12;
                b = b | (src[i++] & 63)<< 6;
                b = b | (src[i++] & 63);
            } else if (b >= 192) {
                b = (b & 31)<< 6;
                b = b | (src[i++] & 63);
            }
            dst[j++] = (char) b;
        }
        return j;
    }

    /**
      * Return bytes in Utf8 representation as an array of characters.
      *  @param src        The array holding the bytes.
      *  @param sindex     The start index from which bytes are converted.
      *  @param len        The maximum number of bytes to convert.
      */
    public static char[] utf2chars(byte[] src, int sindex, int len) {
        char[] dst = new char[len];
        int len1 = utf2chars(src, sindex, dst, 0, len);
        char[] result = new char[len1];
        System.arraycopy(dst, 0, result, 0, len1);
        return result;
    }

    /**
      * Return all bytes of a given array in Utf8 representation
      *  as an array of characters.
      *  @param src        The array holding the bytes.
      */
    public static char[] utf2chars(byte[] src) {
        return utf2chars(src, 0, src.length);
    }

    /**
      * Return bytes in Utf8 representation as a string.
      *  @param src        The array holding the bytes.
      *  @param sindex     The start index from which bytes are converted.
      *  @param len        The maximum number of bytes to convert.
      */
    public static String utf2string(byte[] src, int sindex, int len) {
        char[] dst = new char[len];
        int len1 = utf2chars(src, sindex, dst, 0, len);
        return new String(dst, 0, len1);
    }

    /**
      * Return all bytes of a given array in Utf8 representation
      *  as a string.
      *  @param src        The array holding the bytes.
      */
    public static String utf2string(byte[] src) {
        return utf2string(src, 0, src.length);
    }

    /**
      * Copy characters in source array to bytes in target array,
      *  converting them to Utf8 representation.
      *  The target array must be large enough to hold the result.
      *  returns first index in `dst' past the last copied byte.
      *  @param src        The array holding the characters to convert.
      *  @param sindex     The start index from which characters are converted.
      *  @param dst        The array holding the converted characters..
      *  @param sindex     The start index from which converted bytes
      *                    are written.
      *  @param len        The maximum number of characters to convert.
      */
    public static int chars2utf(char[] src, int sindex, byte[] dst, int dindex,
            int len) {
        int j = dindex;
        int limit = sindex + len;
        for (int i = sindex; i < limit; i++) {
            char ch = src[i];
            if (1 <= ch && ch <= 127) {
                dst[j++] = (byte) ch;
            } else if (ch <= 2047) {
                dst[j++] = (byte)(192 | (ch >> 6));
                dst[j++] = (byte)(128 | (ch & 63));
            } else {
                dst[j++] = (byte)(224 | (ch >> 12));
                dst[j++] = (byte)(128 | ((ch >> 6) & 63));
                dst[j++] = (byte)(128 | (ch & 63));
            }
        }
        return j;
    }

    /**
      * Return characters as an array of bytes in Utf8 representation.
      *  @param src        The array holding the characters.
      *  @param sindex     The start index from which characters are converted.
      *  @param len        The maximum number of characters to convert.
      */
    public static byte[] chars2utf(char[] src, int sindex, int len) {
        byte[] dst = new byte[len * 3];
        int len1 = chars2utf(src, sindex, dst, 0, len);
        byte[] result = new byte[len1];
        System.arraycopy(dst, 0, result, 0, len1);
        return result;
    }

    /**
      * Return all characters in given array as an array of bytes
      *  in Utf8 representation.
      *  @param src        The array holding the characters.
      */
    public static byte[] chars2utf(char[] src) {
        return chars2utf(src, 0, src.length);
    }

    /**
      * Return string as an array of bytes in in Utf8 representation.
      */
    public static byte[] string2utf(String s) {
        return chars2utf(s.toCharArray());
    }

    /**
      * Quote all non-printing characters in string, but leave unicode
      *  characters alone.
      */
    public static String quote(String s) {
        StringBuffer buf = new StringBuffer();
        for (int i = 0; i < s.length(); i++) {
            char ch = s.charAt(i);
            switch (ch) {
            case '\n':
                buf.append("\\n");
                break;

            case '\t':
                buf.append("\\t");
                break;

            case '\b':
                buf.append("\\b");
                break;

            case '\f':
                buf.append("\\f");
                break;

            case '\r':
                buf.append("\\r");
                break;

            case '\"':
                buf.append("\\\"");
                break;

            case '\'':
                buf.append("\\\'");
                break;

            case '\\':
                buf.append("\\\\");
                break;

            default:
                if (ch < 32 || 128 <= ch && ch < 255) {
                    buf.append("\\");
                    buf.append((char)('0' + (ch >> 6) % 8));
                    buf.append((char)('0' + (ch >> 3) % 8));
                    buf.append((char)('0' + (ch) % 8));
                } else {
                    buf.append(ch);
                }

            }
        }
        return buf.toString();
    }

    /**
      * Escape all unicode characters in string.
      */
    public static String escapeUnicode(String s) {
        int len = s.length();
        int i = 0;
        while (i < len) {
            char ch = s.charAt(i);
            if (ch > 255) {
                StringBuffer buf = new StringBuffer();
                buf.append(s.substring(0, i));
                while (i < len) {
                    ch = s.charAt(i);
                    if (ch > 255) {
                        buf.append("\\u");
                        Character.forDigit((ch >> 12) % 16, 16);
                        Character.forDigit((ch >> 8) % 16, 16);
                        Character.forDigit((ch >> 4) % 16, 16);
                        Character.forDigit((ch) % 16, 16);
                    } else {
                        buf.append(ch);
                    }
                    i++;
                }
                s = buf.toString();
            } else {
                i++;
            }
        }
        return s;
    }

    /**
      * Return the last part of a class name.
      */
    public static Name shortName(Name classname) {
        return classname.subName(classname.lastIndexOf((byte)'.') + 1, classname.len);
    }

    /**
      * Return the package name of a class name, excluding the trailing '.',
      *  "" if not existent.
      */
    public static Name packagePart(Name classname) {
        return classname.subName(0, classname.lastIndexOf((byte)'.'));
    }
}