com.alibaba.fastjson.util.IOUtils#UTF8 ( )源码实例Demo

/**
 * @since 1.2.11
 */
@SuppressWarnings("unchecked")
public static <T> T parseObject(byte[] bytes, int offset, int len, Charset charset, Type clazz, Feature... features) {
    if (charset == null) {
        charset = IOUtils.UTF8;
    }
    
    String strVal;
    if (charset == IOUtils.UTF8) {
        char[] chars = allocateChars(bytes.length);
        int chars_len = IOUtils.decodeUTF8(bytes, offset, len, chars);
        if (chars_len < 0) {
            return null;
        }
        strVal = new String(chars, 0, chars_len);
    } else {
        if (len < 0) {
            return null;
        }
        strVal = new String(bytes, offset, len, charset);
    }
    return (T) parseObject(strVal, clazz, features);
}
 

public int writeToEx(OutputStream out, Charset charset) throws IOException {
    if (this.writer != null) {
        throw new UnsupportedOperationException("writer not null");
    }
    
    if (charset == IOUtils.UTF8) {
        return encodeToUTF8(out);
    } else {
        byte[] bytes = new String(buf, 0, count).getBytes(charset);
        out.write(bytes);
        return bytes.length;
    }
}
 

public byte[] toBytes(Charset charset) {
    if (this.writer != null) {
        throw new UnsupportedOperationException("writer not null");
    }
    
    if (charset == IOUtils.UTF8) {
        return encodeToUTF8Bytes();
    } else {
        return new String(buf, 0, count).getBytes(charset);
    }
}
 

/**
 * @since 1.2.11
 */
@SuppressWarnings("unchecked")
public static <T> T parseObject(InputStream is, //
                                Charset charset, //
                                Type type, //
                                Feature... features) throws IOException {
    if (charset == null) {
        charset = IOUtils.UTF8;
    }
    
    byte[] bytes = allocateBytes(1024 * 64);
    int offset = 0;
    for (;;) {
        int readCount = is.read(bytes, offset, bytes.length - offset);
        if (readCount == -1) {
            break;
        }
        offset += readCount;
        if (offset == bytes.length) {
            byte[] newBytes = new byte[bytes.length * 3 / 2];
            System.arraycopy(bytes, 0, newBytes, 0, bytes.length);
            bytes = newBytes;
        }
    }
    
    return (T) parseObject(bytes, 0, offset, charset, type, features);
}