import java.io.*;

public class DataInputStream2 extends DataInputStream {

    public DataInputStream2(InputStream in) {
        super(in);
    }

    public final String readUTF2() throws IOException {
        return readUTF2(this);
    }

    public final static String readUTF2(DataInput in) throws IOException {
        int utflen = in.readUnsignedShort();
        char str[] = new char[utflen];
        int count = 0;
        int strlen = 0;
        while (count < utflen) {
            int c = in.readUnsignedByte();
            int char2, char3;
            switch (c >> 4) { 
                case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7:
                    // 0xxxxxxx
                    count++;
                    str[strlen++] = (char)c;
                    break;
                case 12: case 13:
                    // 110x xxxx   10xx xxxx
                    count += 2;
                    if (count > utflen) 
                        throw new UTFDataFormatException();               
                    char2 = in.readUnsignedByte();
                    if ((char2 & 0xC0) != 0x80)
                        throw new UTFDataFormatException();               
                    str[strlen++] = (char)(((c & 0x1F) << 6) | (char2 & 0x3F));
                    break;
                case 14:
                    // 1110 xxxx  10xx xxxx  10xx xxxx
                    count += 3;
                    if (count > utflen) 
                        throw new UTFDataFormatException();               
                    char2 = in.readUnsignedByte();
                    char3 = in.readUnsignedByte();
                    if (((char2 & 0xC0) != 0x80) || ((char3 & 0xC0) != 0x80))
                        throw new UTFDataFormatException();               
                    str[strlen++] = (char)(((c & 0x0F) << 12) |
                                           ((char2 & 0x3F) << 6) |
                                           ((char3 & 0x3F) << 0));
                    break; // <- lack of this statement!
                default:
                    // 10xx xxxx,  1111 xxxx
                    throw new UTFDataFormatException();           
                }
        }
        return new String(str, 0, strlen);
    }
}