bytechunk.java

业界著名的tomcat服务器的最新6.0的源代码。

        System.arraycopy(buff, start, src, off, n);
        start += n;
        return n;

    }


    /** Send the buffer to the sink. Called by append() when the limit is reached.
     *  You can also call it explicitely to force the data to be written.
     *
     * @throws IOException
     */
    public void flushBuffer()
	throws IOException
    {
	//assert out!=null
	if( out==null ) {
	    throw new IOException( "Buffer overflow, no sink " + limit + " " +
				   buff.length  );
	}
	out.realWriteBytes( buff, start, end-start );
	end=start;
    }

    /** Make space for len chars. If len is small, allocate
     *	a reserve space too. Never grow bigger than limit.
     */
    private void makeSpace(int count)
    {
	byte[] tmp = null;

	int newSize;
	int desiredSize=end + count;

	// Can't grow above the limit
	if( limit > 0 &&
	    desiredSize > limit) {
	    desiredSize=limit;
	}

	if( buff==null ) {
	    if( desiredSize < 256 ) desiredSize=256; // take a minimum
	    buff=new byte[desiredSize];
	}
	
	// limit < buf.length ( the buffer is already big )
	// or we already have space XXX
	if( desiredSize <= buff.length ) {
	    return;
	}
	// grow in larger chunks
	if( desiredSize < 2 * buff.length ) {
	    newSize= buff.length * 2;
	    if( limit >0 &&
		newSize > limit ) newSize=limit;
	    tmp=new byte[newSize];
	} else {
	    newSize= buff.length * 2 + count ;
	    if( limit > 0 &&
		newSize > limit ) newSize=limit;
	    tmp=new byte[newSize];
	}
	
	System.arraycopy(buff, start, tmp, 0, end-start);
	buff = tmp;
	tmp = null;
	end=end-start;
	start=0;
    }
    
    // -------------------- Conversion and getters --------------------

    public String toString() {
        if (null == buff) {
            return null;
        } else if (end-start == 0) {
            return "";
        }
        return StringCache.toString(this);
    }
    
    public String toStringInternal() {
        String strValue=null;
        try {
            if( enc==null ) enc=DEFAULT_CHARACTER_ENCODING;
            strValue = new String( buff, start, end-start, enc );
            /*
             Does not improve the speed too much on most systems,
             it's safer to use the "clasical" new String().
             
             Most overhead is in creating char[] and copying,
             the internal implementation of new String() is very close to
             what we do. The decoder is nice for large buffers and if
             we don't go to String ( so we can take advantage of reduced GC)
             
             // Method is commented out, in:
              return B2CConverter.decodeString( enc );
              */
        } catch (java.io.UnsupportedEncodingException e) {
            // Use the platform encoding in that case; the usage of a bad
            // encoding will have been logged elsewhere already
            strValue = new String(buff, start, end-start);
        }
        return strValue;
    }

    public int getInt()
    {
	return Ascii.parseInt(buff, start,end-start);
    }

    public long getLong() {
        return Ascii.parseLong(buff, start,end-start);
    }


    // -------------------- equals --------------------

    /**
     * Compares the message bytes to the specified String object.
     * @param s the String to compare
     * @return true if the comparison succeeded, false otherwise
     */
    public boolean equals(String s) {
	// XXX ENCODING - this only works if encoding is UTF8-compat
	// ( ok for tomcat, where we compare ascii - header names, etc )!!!
	
	byte[] b = buff;
	int blen = end-start;
	if (b == null || blen != s.length()) {
	    return false;
	}
	int boff = start;
	for (int i = 0; i < blen; i++) {
	    if (b[boff++] != s.charAt(i)) {
		return false;
	    }
	}
	return true;
    }

    /**
     * Compares the message bytes to the specified String object.
     * @param s the String to compare
     * @return true if the comparison succeeded, false otherwise
     */
    public boolean equalsIgnoreCase(String s) {
	byte[] b = buff;
	int blen = end-start;
	if (b == null || blen != s.length()) {
	    return false;
	}
	int boff = start;
	for (int i = 0; i < blen; i++) {
	    if (Ascii.toLower(b[boff++]) != Ascii.toLower(s.charAt(i))) {
		return false;
	    }
	}
	return true;
    }

    public boolean equals( ByteChunk bb ) {
	return equals( bb.getBytes(), bb.getStart(), bb.getLength());
    }
    
    public boolean equals( byte b2[], int off2, int len2) {
	byte b1[]=buff;
	if( b1==null && b2==null ) return true;

	int len=end-start;
	if ( len2 != len || b1==null || b2==null ) 
	    return false;
		
	int off1 = start;

	while ( len-- > 0) {
	    if (b1[off1++] != b2[off2++]) {
		return false;
	    }
	}
	return true;
    }

    public boolean equals( CharChunk cc ) {
	return equals( cc.getChars(), cc.getStart(), cc.getLength());
    }
    
    public boolean equals( char c2[], int off2, int len2) {
	// XXX works only for enc compatible with ASCII/UTF !!!
	byte b1[]=buff;
	if( c2==null && b1==null ) return true;
	
	if (b1== null || c2==null || end-start != len2 ) {
	    return false;
	}
	int off1 = start;
	int len=end-start;
	
	while ( len-- > 0) {
	    if ( (char)b1[off1++] != c2[off2++]) {
		return false;
	    }
	}
	return true;
    }

    /**
     * Returns true if the message bytes starts with the specified string.
     * @param s the string
     */
    public boolean startsWith(String s) {
	// Works only if enc==UTF
	byte[] b = buff;
	int blen = s.length();
	if (b == null || blen > end-start) {
	    return false;
	}
	int boff = start;
	for (int i = 0; i < blen; i++) {
	    if (b[boff++] != s.charAt(i)) {
		return false;
	    }
	}
	return true;
    }

    /* Returns true if the message bytes start with the specified byte array */
    public boolean startsWith(byte[] b2) {
        byte[] b1 = buff;
        if (b1 == null && b2 == null) {
            return true;
        }

        int len = end - start;
        if (b1 == null || b2 == null || b2.length > len) {
            return false;
        }
        for (int i = start, j = 0; i < end && j < b2.length; ) {
            if (b1[i++] != b2[j++]) 
                return false;
        }
        return true;
    }

    /**
     * Returns true if the message bytes starts with the specified string.
     * @param s the string
     * @param pos The position
     */
    public boolean startsWithIgnoreCase(String s, int pos) {
	byte[] b = buff;
	int len = s.length();
	if (b == null || len+pos > end-start) {
	    return false;
	}
	int off = start+pos;
	for (int i = 0; i < len; i++) {
	    if (Ascii.toLower( b[off++] ) != Ascii.toLower( s.charAt(i))) {
		return false;
	    }
	}
	return true;
    }

    public int indexOf( String src, int srcOff, int srcLen, int myOff ) {
	char first=src.charAt( srcOff );

	// Look for first char 
	int srcEnd = srcOff + srcLen;
        
	for( int i=myOff+start; i <= (end - srcLen); i++ ) {
	    if( buff[i] != first ) continue;
	    // found first char, now look for a match
            int myPos=i+1;
	    for( int srcPos=srcOff + 1; srcPos< srcEnd; ) {
                if( buff[myPos++] != src.charAt( srcPos++ ))
		    break;
                if( srcPos==srcEnd ) return i-start; // found it
	    }
	}
	return -1;
    }

    // -------------------- Hash code  --------------------

    // normal hash. 
    public int hash() {
	return hashBytes( buff, start, end-start);
    }

    // hash ignoring case
    public int hashIgnoreCase() {
	return hashBytesIC( buff, start, end-start );
    }

    private static int hashBytes( byte buff[], int start, int bytesLen ) {
	int max=start+bytesLen;
	byte bb[]=buff;
	int code=0;
	for (int i = start; i < max ; i++) {
	    code = code * 37 + bb[i];
	}
	return code;
    }

    private static int hashBytesIC( byte bytes[], int start,
				    int bytesLen )
    {
	int max=start+bytesLen;
	byte bb[]=bytes;
	int code=0;
	for (int i = start; i < max ; i++) {
	    code = code * 37 + Ascii.toLower(bb[i]);
	}
	return code;
    }

    /**
     * Returns true if the message bytes starts with the specified string.
     * @param c the character
     * @param starting The start position
     */
    public int indexOf(char c, int starting) {
	int ret = indexOf( buff, start+starting, end, c);
	return (ret >= start) ? ret - start : -1;
    }

    public static int  indexOf( byte bytes[], int off, int end, char qq )
    {
	// Works only for UTF 
	while( off < end ) {
	    byte b=bytes[off];
	    if( b==qq )
		return off;
	    off++;
	}
	return -1;
    }

    /** Find a character, no side effects.
     *  @return index of char if found, -1 if not
     */
    public static int findChar( byte buf[], int start, int end, char c ) {
	byte b=(byte)c;
	int offset = start;
	while (offset < end) {
	    if (buf[offset] == b) {
		return offset;
	    }
	    offset++;
	}
	return -1;
    }

    /** Find a character, no side effects.
     *  @return index of char if found, -1 if not
     */
    public static int findChars( byte buf[], int start, int end, byte c[] ) {
	int clen=c.length;
	int offset = start;
	while (offset < end) {
	    for( int i=0; i<clen; i++ ) 
		if (buf[offset] == c[i]) {
		    return offset;
		}
	    offset++;
	}
	return -1;
    }

    /** Find the first character != c 
     *  @return index of char if found, -1 if not
     */
    public static int findNotChars( byte buf[], int start, int end, byte c[] )
    {
	int clen=c.length;
	int offset = start;
	boolean found;
		
	while (offset < end) {
	    found=true;
	    for( int i=0; i<clen; i++ ) {
		if (buf[offset] == c[i]) {
		    found=false;
		    break;
		}
	    }
	    if( found ) { // buf[offset] != c[0..len]
		return offset;
	    }
	    offset++;
	}
	return -1;
    }


    /**
     * Convert specified String to a byte array. This ONLY WORKS for ascii, UTF chars will be truncated.
     * 
     * @param value to convert to byte array
     * @return the byte array value
     */
    public static final byte[] convertToBytes(String value) {
        byte[] result = new byte[value.length()];
        for (int i = 0; i < value.length(); i++) {
            result[i] = (byte) value.charAt(i);
        }
        return result;
    }
    
    
}