UTF-8 Encoder/Decoder

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UTF-8 Encoder / Decoder

Since some of the phones don't support UTF-8, I have my own UTF-8 encoder / decoder. I like to share it with others. Please, don't PM me or email for any help regarding this code.

You can use these two methods in any of your class.

/*

Author : Shivakumar
Mail   : shiva (at) blisspark.com
Disclaimer : This code is provided without any implied or expressed warranty and may not work as 
expected. If have any bugs, inform me or post the fix here.

*/

public static String UTF8Decode(byte in[], int offset, int length)
{
	StringBuffer buff = new StringBuffer();
	int max = offset + length;
	for( int i = offset ; i < max ; i++)
	{
		char c = 0;
		if((in[i] & 0x80) == 0)
		{
			c = (char) in[i];
		}
		else if(( in[i] & 0xe0 ) == 0xc0)	// 11100000
		{
			c |= ((in[i] & 0x1f) << 6);		// 00011111
			i++;
			c |= ((in[i] & 0x3f) << 0);		// 00111111
		}
		else if(( in[i] & 0xf0) == 0xe0)	// 11110000
		{
			c |= ((in[i] & 0x0f) << 12);	// 00001111
			i++;
			c |= ((in[i] & 0x3f) << 6);		// 00111111
			i++;
			c |= ((in[i] & 0x3f) << 0);		// 00111111
		}
		else if((in[i] & 0xf8) == 0xf0)		// 11111000
		{
			c |= ((in[i] & 0x07) << 18);	// 00000111 (move 18, not 16?)
			i++;
			c |= ((in[i] & 0x3f) << 12);	// 00111111
			i++;
			c |= ((in[i] & 0x3f) << 6);		// 00111111
			i++;
			c |= ((in[i] & 0x3f) << 0);		// 00111111
		}
		else
		{
			c = '?';
		}
		buff.append(c);
	}
	return buff.toString();
}

public static byte[] UTF8Encode(String str)
{
	ByteArrayOutputStream bos = new ByteArrayOutputStream();
	try
	{
		int strlen = str.length();

		for( int i = 0 ; i < strlen ; i++ )
		{
			char t = str.charAt(i);
			int c = t & 0xffff;

			if(c >= 0 && c < 0x80)
			{
				bos.write((byte)( c & 0xff ));
			}
			else if(c > 0x7f && c < 0x800)
			{
				bos.write( (byte) ((( c >>> 6 ) & 0x1f ) | 0xc0 ));
				bos.write( (byte) ((( c >>> 0 ) & 0x3f ) | 0x80 ));
			}
			else if(c > 0x7ff && c < 0x10000)
			{
				bos.write( (byte) ((( c >>> 12 ) & 0x0f ) | 0xe0 )); // <-- correction (mb)
				bos.write( (byte) ((( c >>> 6 ) & 0x3f ) | 0x80 ));
				bos.write( (byte) ((( c >>> 0 ) & 0x3f ) | 0x80 ));
			}
			else if(c > 0x00ffff && c < 0xfffff)
			{
				bos.write( (byte) ((( c >>> 18 ) & 0x07 ) | 0xf0 ));
				bos.write( (byte) ((( c >>> 12 ) & 0x3f ) | 0x80 ));
				bos.write( (byte) ((( c >>> 6 ) & 0x3f ) | 0x80 ));
				bos.write( (byte) ((( c >>> 0 ) & 0x3f ) | 0x80 ));
			}
		}
		bos.flush();
	}
	catch(Exception e)
	{
	}
	return bos.toByteArray();
}

Shivakumar Ramachandhran
09:26, 22 Jul 2006 (EEST)

Matt Bucknall (matt (at) mattbucknall.com (http://www.mattbucknall.com))
22 Apr 2007: Changed '... | 0x70' to '... | 0xe0' in UTF8Encode

Sam Mason (sam (at) samason.me.uk)
18 Dec 2008: Changed initialisation of variable "c" in the Encoder() function. I'm unsure why it's being masked with 0xffff as well, should that be 0xfffff (i.e. is it missing an 'f' on the end?)

John Campbell (IP (http://www.ipsupermarket.com))
I think this page should be protected from spam keywords / text injection.