GWT Native Base64

Here is the code:

public static native String Base64Encode(String data) /*-{
function encode_base64(data) {
var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
var out = "", c1, c2, c3, e1, e2, e3, e4;
for (var i = 0; i < data.length; ) {
c1 = data.charCodeAt(i++);
c2 = data.charCodeAt(i++);
c3 = data.charCodeAt(i++);
e1 = c1 >> 2;
e2 = ((c1 & 3) << 4) + (c2 >> 4);
e3 = ((c2 & 15) << 2) + (c3 >> 6);
e4 = c3 & 63;
if (isNaN(c2))
e3 = e4 = 64;
else if (isNaN(c3))
e4 = 64;
out += tab.charAt(e1) + tab.charAt(e2) + tab.charAt(e3) + tab.charAt(e4);
}
return out;
}
return encode_base64(data);
}-*/;

public static native String Base64Decode(String data)/*-{
function decode_base64(data) {
var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
var out = "", c1, c2, c3, e1, e2, e3, e4;
for (var i = 0; i < data.length; ) {
e1 = tab.indexOf(data.charAt(i++));
e2 = tab.indexOf(data.charAt(i++));
e3 = tab.indexOf(data.charAt(i++));
e4 = tab.indexOf(data.charAt(i++));
c1 = (e1 << 2) + (e2 >> 4);
c2 = ((e2 & 15) << 4) + (e3 >> 2);
c3 = ((e3 & 3) << 6) + e4;
out += String.fromCharCode(c1);
if (e3 != 64)
out += String.fromCharCode(c2);
if (e4 != 64)
out += String.fromCharCode(c3);
}
return out;
}
return decode_base64(data);
}-*/;