#vulnerable code 
                                @NotNull
    @Override
    public String readUTF() {
        try {
            int len = readUnsignedShort();
            StringBuilder utfReader = acquireStringBuilder();
            readUTF0(utfReader, len);
            return utfReader.length() == 0 ? "" : stringInterner().intern(utfReader);
        } catch (IOException unexpected) {
            throw new AssertionError(unexpected);
        }
    } 
                            #location 8 
                            #vulnerability type THREAD_SAFETY_VIOLATION
#fixed code
                                @NotNull
    @Override
    public String readUTF() {
        try {
            int len = readUnsignedShort();
            StringBuilder utfReader = acquireStringBuilder();
            readUTF0(utfReader, len);
            return utfReader.length() == 0 ? "" : SI.intern(utfReader);
        } catch (IOException unexpected) {
            throw new AssertionError(unexpected);
        }
    }