/**
* Decode String with % encoding. This method makes the assumption that the majority of calls will
* need no decoding.
*/
public static String decodeString(String encoded, int offset, int length, String charset) {
if (charset == null || StringUtil.isUTF8(charset)) {
Utf8StringBuffer buffer = null;
for (int i = 0; i < length; i++) {
char c = encoded.charAt(offset + i);
if (c < 0 || c > 0xff) {
if (buffer == null) {
buffer = new Utf8StringBuffer(length);
buffer.getStringBuffer().append(encoded, offset, offset + i + 1);
} else buffer.getStringBuffer().append(c);
} else if (c == '+') {
if (buffer == null) {
buffer = new Utf8StringBuffer(length);
buffer.getStringBuffer().append(encoded, offset, offset + i);
}
buffer.getStringBuffer().append(' ');
} else if (c == '%' && (i + 2) < length) {
if (buffer == null) {
buffer = new Utf8StringBuffer(length);
buffer.getStringBuffer().append(encoded, offset, offset + i);
}
try {
byte b = (byte) TypeUtil.parseInt(encoded, offset + i + 1, 2, 16);
buffer.append(b);
i += 2;
} catch (NumberFormatException nfe) {
buffer.getStringBuffer().append('%');
}
} else if (buffer != null) buffer.getStringBuffer().append(c);
}
if (buffer == null) {
if (offset == 0 && encoded.length() == length) return encoded;
return encoded.substring(offset, offset + length);
}
return buffer.toString();
} else {
StringBuffer buffer = null;
try {
for (int i = 0; i < length; i++) {
char c = encoded.charAt(offset + i);
if (c < 0 || c > 0xff) {
if (buffer == null) {
buffer = new StringBuffer(length);
buffer.append(encoded, offset, offset + i + 1);
} else buffer.append(c);
} else if (c == '+') {
if (buffer == null) {
buffer = new StringBuffer(length);
buffer.append(encoded, offset, offset + i);
}
buffer.append(' ');
} else if (c == '%' && (i + 2) < length) {
if (buffer == null) {
buffer = new StringBuffer(length);
buffer.append(encoded, offset, offset + i);
}
byte[] ba = new byte[length];
int n = 0;
while (c >= 0 && c <= 0xff) {
if (c == '%') {
if (i + 2 < length) {
try {
ba[n++] = (byte) TypeUtil.parseInt(encoded, offset + i + 1, 2, 16);
i += 3;
} catch (NumberFormatException nfe) {
ba[n - 1] = (byte) '%';
for (char next; ((next = encoded.charAt(++i + offset)) != '%'); )
ba[n++] = (byte) (next == '+' ? ' ' : next);
}
} else {
ba[n++] = (byte) '%';
i++;
}
} else if (c == '+') {
ba[n++] = (byte) ' ';
i++;
} else {
ba[n++] = (byte) c;
i++;
}
if (i >= length) break;
c = encoded.charAt(offset + i);
}
i--;
buffer.append(new String(ba, 0, n, charset));
} else if (buffer != null) buffer.append(c);
}
if (buffer == null) {
if (offset == 0 && encoded.length() == length) return encoded;
return encoded.substring(offset, offset + length);
}
return buffer.toString();
} catch (UnsupportedEncodingException e) {
throw new RuntimeException(e);
}
}
}
