Jetty example source code file (StringUtil.java)

This example Jetty source code file (StringUtil.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Jetty tags/keywords

crlf, io, iso-8859-1, iso8859_1, string, string, stringbuffer, stringbuffer, stringutil, unsupportedencodingexception, unsupportedencodingexception, utf-16, utf-8, utf8stringbuffer, utf8stringbuffer

The Jetty StringUtil.java source code

// ========================================================================
// Copyright 2004-2005 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at 
// http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ========================================================================

package org.mortbay.util;

import java.io.UnsupportedEncodingException;

// ====================================================================
/** Fast String Utilities.
 *
 * These string utilities provide both conveniance methods and
 * performance improvements over most standard library versions. The
 * main aim of the optimizations is to avoid object creation unless
 * absolutely required.
 *
 * @author Greg Wilkins (gregw)
 */
public class StringUtil
{
    public static final String CRLF="\015\012";
    public static final String __LINE_SEPARATOR=
        System.getProperty("line.separator","\n");
    
    public static String __ISO_8859_1;
    static
    {
        String iso=System.getProperty("ISO_8859_1");
        if (iso!=null)
            __ISO_8859_1=iso;
        else
        {
            try{
                new String(new byte[]{(byte)20},"ISO-8859-1");
                __ISO_8859_1="ISO-8859-1";
            }
            catch(java.io.UnsupportedEncodingException e)
            {
                __ISO_8859_1="ISO8859_1";
            }        
        }
    }
    
    public final static String __UTF8="UTF-8";
    public final static String __UTF16="UTF-16";
    
    
    private static char[] lowercases = {
          '\000','\001','\002','\003','\004','\005','\006','\007',
          '\010','\011','\012','\013','\014','\015','\016','\017',
          '\020','\021','\022','\023','\024','\025','\026','\027',
          '\030','\031','\032','\033','\034','\035','\036','\037',
          '\040','\041','\042','\043','\044','\045','\046','\047',
          '\050','\051','\052','\053','\054','\055','\056','\057',
          '\060','\061','\062','\063','\064','\065','\066','\067',
          '\070','\071','\072','\073','\074','\075','\076','\077',
          '\100','\141','\142','\143','\144','\145','\146','\147',
          '\150','\151','\152','\153','\154','\155','\156','\157',
          '\160','\161','\162','\163','\164','\165','\166','\167',
          '\170','\171','\172','\133','\134','\135','\136','\137',
          '\140','\141','\142','\143','\144','\145','\146','\147',
          '\150','\151','\152','\153','\154','\155','\156','\157',
          '\160','\161','\162','\163','\164','\165','\166','\167',
          '\170','\171','\172','\173','\174','\175','\176','\177' };

    /* ------------------------------------------------------------ */
    /**
     * fast lower case conversion. Only works on ascii (not unicode)
     * @param s the string to convert
     * @return a lower case version of s
     */
    public static String asciiToLowerCase(String s)
    {
        char[] c = null;
        int i=s.length();

        // look for first conversion
        while (i-->0)
        {
            char c1=s.charAt(i);
            if (c1<=127)
            {
                char c2=lowercases[c1];
                if (c1!=c2)
                {
                    c=s.toCharArray();
                    c[i]=c2;
                    break;
                }
            }
        }

        while (i-->0)
        {
            if(c[i]<=127)
                c[i] = lowercases[c[i]];
        }
        
        return c==null?s:new String(c);
    }


    /* ------------------------------------------------------------ */
    public static boolean startsWithIgnoreCase(String s,String w)
    {
        if (w==null)
            return true;
        
        if (s==null || s.length()<w.length())
            return false;
        
        for (int i=0;i<w.length();i++)
        {
            char c1=s.charAt(i);
            char c2=w.charAt(i);
            if (c1!=c2)
            {
                if (c1<=127)
                    c1=lowercases[c1];
                if (c2<=127)
                    c2=lowercases[c2];
                if (c1!=c2)
                    return false;
            }
        }
        return true;
    }
    
    /* ------------------------------------------------------------ */
    public static boolean endsWithIgnoreCase(String s,String w)
    {
        if (w==null)
            return true;

        if (s==null)
            return false;
            
        int sl=s.length();
        int wl=w.length();
        
        if (sl<wl)
            return false;
        
        for (int i=wl;i-->0;)
        {
            char c1=s.charAt(--sl);
            char c2=w.charAt(i);
            if (c1!=c2)
            {
                if (c1<=127)
                    c1=lowercases[c1];
                if (c2<=127)
                    c2=lowercases[c2];
                if (c1!=c2)
                    return false;
            }
        }
        return true;
    }
    
    /* ------------------------------------------------------------ */
    /**
     * returns the next index of a character from the chars string
     */
    public static int indexFrom(String s,String chars)
    {
        for (int i=0;i<s.length();i++)
           if (chars.indexOf(s.charAt(i))>=0)
              return i;
        return -1;
    }
    
    /* ------------------------------------------------------------ */
    /**
     * replace substrings within string.
     */
    public static String replace(String s, String sub, String with)
    {
        int c=0;
        int i=s.indexOf(sub,c);
        if (i == -1)
            return s;
    
        StringBuffer buf = new StringBuffer(s.length()+with.length());

        synchronized(buf)
        {
            do
            {
                buf.append(s.substring(c,i));
                buf.append(with);
                c=i+sub.length();
            } while ((i=s.indexOf(sub,c))!=-1);
            
            if (c<s.length())
                buf.append(s.substring(c,s.length()));
            
            return buf.toString();
        }
    }


    /* ------------------------------------------------------------ */
    /** Remove single or double quotes.
     */
    public static String unquote(String s)
    {
        return QuotedStringTokenizer.unquote(s);
    }


    /* ------------------------------------------------------------ */
    /** Append substring to StringBuffer 
     * @param buf StringBuffer to append to
     * @param s String to append from
     * @param offset The offset of the substring
     * @param length The length of the substring
     */
    public static void append(StringBuffer buf,
                              String s,
                              int offset,
                              int length)
    {
        synchronized(buf)
        {
            int end=offset+length;
            for (int i=offset; i<end;i++)
            {
                if (i>=s.length())
                    break;
                buf.append(s.charAt(i));
            }
        }
    }

    
    /* ------------------------------------------------------------ */
    /**
     * append hex digit
     * 
     */
    public static void append(StringBuffer buf,byte b,int base)
    {
        int bi=0xff&b;
        int c='0'+(bi/base)%base;
        if (c>'9')
            c= 'a'+(c-'0'-10);
        buf.append((char)c);
        c='0'+bi%base;
        if (c>'9')
            c= 'a'+(c-'0'-10);
        buf.append((char)c);
    }

    
    /* ------------------------------------------------------------ */
    public static void append2digits(StringBuffer buf,int i)
    {
        if (i<100)
        {
            buf.append((char)(i/10+'0'));
            buf.append((char)(i%10+'0'));
        }
    }
    
    /* ------------------------------------------------------------ */
    /** Return a non null string.
     * @param s String
     * @return The string passed in or empty string if it is null. 
     */
    public static String nonNull(String s)
    {
        if (s==null)
            return "";
        return s;
    }
    
    /* ------------------------------------------------------------ */
    public static boolean equals(String s,char[] buf, int offset, int length)
    {
        if (s.length()!=length)
            return false;
        for (int i=0;i<length;i++)
            if (buf[offset+i]!=s.charAt(i))
                return false;
        return true;
    }

    /* ------------------------------------------------------------ */
    public static String toUTF8String(byte[] b,int offset,int length)
    {
        try
        {
            if (length<32)
            {
                Utf8StringBuffer buffer = new Utf8StringBuffer(length);
                buffer.append(b,offset,length);
                return buffer.toString();
            }
            
            return new String(b,offset,length,__UTF8);
        }
        catch (UnsupportedEncodingException e)
        {
            e.printStackTrace();
            return null;
        }
    }

    /* ------------------------------------------------------------ */
    public static String toString(byte[] b,int offset,int length,String charset)
    {
        if (charset==null || StringUtil.isUTF8(charset))
            return toUTF8String(b,offset,length);
        
        try
        {
            return new String(b,offset,length,charset);
        }
        catch (UnsupportedEncodingException e)
        {
            e.printStackTrace();
            return null;
        }
    }


    /* ------------------------------------------------------------ */
    public static boolean isUTF8(String charset)
    {
        return charset==__UTF8 || __UTF8.equalsIgnoreCase(charset);
    }


    /* ------------------------------------------------------------ */
    public static String printable(String name)
    {
        if (name==null)
            return null;
        StringBuffer buf = new StringBuffer(name.length());
        for (int i=0;i<name.length();i++)
        {
            char c=name.charAt(i);
            if (!Character.isISOControl(c))
                buf.append(c);
        }
        return buf.toString();
    }
    
    
}