public abstract class JSON {
    public static parseObject(byte[] input, int off, int len, CharsetDecoder charsetDecoder, Type clazz,
                                      Feature... features) { ... }
    public static Object parse(byte[] input, int off, int len, CharsetDecoder charsetDecoder, 
                                      int features) {}
    public static Object parse(byte[] input, int off, int len, CharsetDecoder charsetDecoder, 
                                      Feature...features) {}
    public static Object parse(byte[] input, int off, int len, CharsetDecoder charsetDecoder, 
                                      int features) {}
}
// JSONSerializerMap已废弃，不支持
com.alibaba.fastjson.serializer.JSONSerializer.JSONSerializer(JSONSerializerMap)

com.alibaba.fastjson.parser.JavaBeanMapping 使用com.alibaba.fastjson.parser.ParserConfig代替
com.alibaba.fastjson.serializer.JSONSerializerMap  使用com.alibaba.fastjson.serializer.SerializeConfig代替
com.alibaba.fastjson.parser.DefaultExtJSONParser 使用com.alibaba.fastjson.parser.DefaultJSONParser代替

class com.alibaba.fastjson.JSONWriter {
    @Deprecated
    public void writeStartObject();
    
    @Deprecated
    public void writeEndObject();
    @Deprecated
    public void writeStartArray();
    
    @Deprecated
    public void writeEndArray();
}