channelbuffer.java

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		return i;
    }

    // 2000-06-05 Fixed
    final long readLongLong() {
        

        long l = (this.directBuffer.get() & 0xff)
        | ((long) (this.directBuffer.get() & 0xff) << 8)
        | ((long) (this.directBuffer.get() & 0xff) << 16)
        | ((long) (this.directBuffer.get() & 0xff) << 24)
        | ((long) (this.directBuffer.get() & 0xff) << 32)
        | ((long) (this.directBuffer.get() & 0xff) << 40)
        | ((long) (this.directBuffer.get() & 0xff) << 48)
        | ((long) (this.directBuffer.get() & 0xff) << 56);
        
		//this.directBuffer.position(this.position);
        
		return l;
    }

    //
    // Read a null-terminated string
    //
    // To avoid alloc'ing a new byte array, we
    // do this by hand, rather than calling getNullTerminatedBytes()
    //
    final String readString() {
        
        int len = 0;
		int maxLen = getBufLength();
		int oldPosition = getPosition();
		
		while ((getPosition() < maxLen) && (this.directBuffer.get() != 0) ) {
            len++;
        }
		
		setPosition(oldPosition);

        String s = new String(bufferToArray(), getPosition(), len);
        
        this.directBuffer.position(getPosition() + len + 1); // update cursor
        
      
        return s;
    }

    final String readString(String encoding) throws SQLException {
       
        int len = 0;

		int maxLen = getBufLength();
		
        while ((getPosition() < maxLen) && (this.directBuffer.get() != 0)) {
            len++;
        }

        try {
            return new String(bufferToArray(), getPosition(), len, encoding);
        } catch (UnsupportedEncodingException uEE) {
            throw new SQLException(Messages.getString("ChannelBuffer.0") //$NON-NLS-1$
                + encoding + Messages.getString("ChannelBuffer.1"), SQLError.SQL_STATE_ILLEGAL_ARGUMENT); //$NON-NLS-1$
        } finally {
    		this.directBuffer.position(getPosition() + len + 1); // update cursor
        }
    }

    final int readnBytes() {
        int sw = this.directBuffer.get() & 0xff;
		//this.directBuffer.position(this.position);
		
        switch (sw) {
        case 1:
            return this.directBuffer.get() & 0xff;

        case 2:
            return this.readInt();

        case 3:
            return this.readLongInt();

        case 4:
            return (int) this.readLong();

        default:
            return 255;
        }
    }

    final void writeByte(byte b) throws SQLException {
        ensureCapacity(1);

        this.directBuffer.put(b);
        this.dirty = true;
    }

    // Write a byte array
    final void writeBytesNoNull(byte[] bytes) throws SQLException {
        int len = bytes.length;
        ensureCapacity(len);
        
        this.directBuffer.put(bytes, 0, len);
        this.dirty = true;
    }

    // Write a byte array with the given offset and length
    final void writeBytesNoNull(byte[] bytes, int offset, int length)
        throws SQLException {
        ensureCapacity(length);
        
  
        this.directBuffer.put(bytes, offset, length);
 
        this.dirty = true;
    }
    
    final void writeDouble(double d) throws SQLException {
        long l = Double.doubleToLongBits(d);
        writeLongLong(l);
        this.dirty = true;
    }

    final void writeFieldLength(long length) throws SQLException {
        if (length < 251) {
            writeByte((byte) length);
        } else if (length < 65536L) {
            ensureCapacity(3);
            writeByte((byte) 252);
            writeInt((int) length);
        } else if (length < 16777216L) {
            ensureCapacity(4);
            writeByte((byte) 253);
            writeLongInt((int) length);
        } else {
            ensureCapacity(9);
            writeByte((byte) 254);
            writeLongLong(length);
        }
        
    }

    final void writeFloat(float f) throws SQLException {
    	ensureCapacity(4);
    	
        int i = Float.floatToIntBits(f);

        this.directBuffer.put((byte) (i & 0xff));
		this.directBuffer.put((byte) (i >>> 8));
		this.directBuffer.put((byte) (i >>> 16));
		this.directBuffer.put((byte) (i >>> 24));

		this.dirty = true;
    }

    // 2000-06-05 Changed
    final void writeInt(int i) throws SQLException {
    	ensureCapacity(2);
		this.directBuffer.put((byte) (i & 0xff));
		this.directBuffer.put((byte) (i >>> 8));

		this.dirty = true;
    }

    //	Write a String using the specified character
    // encoding
    final void writeLenBytes(byte[] b) throws SQLException {
        int len = b.length;
        ensureCapacity(len + 9);
        writeFieldLength(len);
        this.directBuffer.put(b, 0, len);

        this.dirty = true;
    }

    //	Write a String using the specified character
    // encoding
    final void writeLenString(String s, String encoding, String serverEncoding, 
    		SingleByteCharsetConverter converter, boolean parserKnowsUnicode)
        throws UnsupportedEncodingException, SQLException {
        byte[] b = null;
       
        if (converter != null) {
            b = converter.toBytes(s);
        } else {
            b = StringUtils.getBytes(s, encoding, serverEncoding, parserKnowsUnicode);
        }

        int len = b.length;
        ensureCapacity(len + 9);
        writeFieldLength(len);
        this.directBuffer.put(b, 0, len);
      
        this.dirty = true;
    }

    // 2000-06-05 Changed
    final void writeLong(long i) throws SQLException {
    	ensureCapacity(4);
    	
		this.directBuffer.put((byte) (i & 0xff));
		this.directBuffer.put((byte) (i >>> 8));
		this.directBuffer.put((byte) (i >>> 16));
		this.directBuffer.put((byte) (i >>> 24));
	
		this.dirty = true;
    }

    // 2000-06-05 Changed
    final void writeLongInt(int i) throws SQLException {
    	ensureCapacity(3);
    	
		this.directBuffer.put((byte) (i & 0xff));
		this.directBuffer.put((byte) (i >>> 8));
		this.directBuffer.put((byte) (i >>> 16));

		this.dirty = true;
    }

    final void writeLongLong(long i) throws SQLException {
    	ensureCapacity(8);
    	
		this.directBuffer.put((byte) (i & 0xff));
		this.directBuffer.put((byte) (i >>> 8));
		this.directBuffer.put((byte) (i >>> 16));
		this.directBuffer.put((byte) (i >>> 24));
		this.directBuffer.put((byte) (i >>> 32));
		this.directBuffer.put((byte) (i >>> 40));
		this.directBuffer.put((byte) (i >>> 48));
		this.directBuffer.put((byte) (i >>> 56));

		this.dirty = true;
    }

    // Write null-terminated string
    final void writeString(String s) throws SQLException {
        ensureCapacity((s.length() * 2) + 1);
        
        writeStringNoNull(s);
        this.directBuffer.put((byte) 0);

        this.dirty = true;
    }

    // Write string, with no termination
    final void writeStringNoNull(String s) throws SQLException {
        int len = s.length();
        ensureCapacity(len * 2);
  
        this.directBuffer.put(s.getBytes(), 0, len);
      
        this.dirty = true;
    }

    // Write a String using the specified character
    // encoding
    final void writeStringNoNull(String s, String encoding, String serverEncoding,
    		boolean parserKnowsUnicode)
        throws UnsupportedEncodingException, SQLException {
        byte[] b = StringUtils.getBytes(s, encoding, serverEncoding, parserKnowsUnicode);

        int len = b.length;
        ensureCapacity(len);

        this.directBuffer.put(b, 0, len);
    
        this.dirty = true;
    }

    void setBufLength(int bufLengthToSet) {
        this.bufLength = bufLengthToSet;
        this.directBuffer.limit(this.bufLength);
        this.dirty = true;
    }

    int getBufLength() {
        return this.directBuffer.limit();
    }

	private byte[] bufferToArray() {
		if (!this.dirty) {
			return this.asBytes;
		} else if (this.directBuffer.hasArray()) {
			this.asBytes = this.directBuffer.array();
			this.dirty = false;
			
			return this.asBytes;
		} else {
			int bufferLength = this.directBuffer.limit();
			
			this.asBytes = new byte[bufferLength];
			
			int oldPosition = getPosition();
			
			this.directBuffer.position(0);
			this.directBuffer.get(this.asBytes, 0, bufferLength);
			this.directBuffer.position(oldPosition);
			this.dirty = false;
			
			return this.asBytes;
		}
	}

	int getCapacity() {
		return this.directBuffer.capacity();
	}

	/* (non-Javadoc)
	 * @see com.mysql.jdbc.Buffer#getBytes(int, int)
	 */
	byte[] getBytes(int offset, int len) {
		byte[] b = new byte[len];
        byte[] nioByteBuffer = bufferToArray();
         
        try {
        
        	System.arraycopy(nioByteBuffer, offset, b, 0, len);
        	//this.position += len; // update cursor
			this.directBuffer.position((offset + len));
        } catch (ArrayIndexOutOfBoundsException aiobex) {
        	throw aiobex;
        }
		
        return b;
	}
}