Generic Reference

Generic reference in dubbo

Generic invocation is mainly used when the client does not have API interface or model class, all POJOs in parameters and return values are represented by Map.Commonly used for framework integration such as: implementing a common service testing framework, all service implementations can be invoked via GenericService.

Use generic invocation via Spring

Declared in the Spring configuration file generic =" true "

<dubbo:reference id="barService" interface="" generic="true" />

In Java code, get barService and start generic invocation:

GenericService barService = (GenericService) applicationContext.getBean("barService");
Object result = barService.$invoke("sayHello", new String[] { "java.lang.String" }, new Object[] { "World" });

Use generic invocation via API

import org.apache.dubbo.rpc.service.GenericService;

// reference remote service
// The instance is very heavy, which encapsulates all the registration center and service provider connection, please cache
ReferenceConfig<GenericService> reference = new ReferenceConfig<GenericService>();
// weak type service interface name
// declared as generic service

// service stub type is also the org.apache.dubbo.rpc.service.GenericService
GenericService genericService = reference.get();

// basic types and Date, List, Map, etc. do not need conversion, direct use them
Object result = genericService.$invoke("sayHello", new String[] {"java.lang.String"}, new Object[] {"world"});

// map POJO parameters, if the return value is POJO will automatically turn into map
Map<String, Object> person = new HashMap<String, Object>();
person.put("name", "xxx");
person.put("password", "yyy");
// if the return value is POJO will automatically turn into map
Object result = genericService.$invoke("findPerson", new String[]
{""}, new Object[]{person});


Further explanation of generalized types

Consider POJO like this:


public class PersonImpl implements Person {
    private String name;
    private String password;

    public String getName() {
        return name;

    public void setName(String name) { = name;

    public String getPassword() {
        return password;

    public void setPassword(String password) {
        this.password = password;

The POJO data:

Person person = new PersonImpl();

Data represented by Map

Map<String, Object> map = new HashMap<String, Object>();
// Note: If the parameter type is an interface, or List lost the generic class, you can specify the type of the class attribute
map.put("class", "");
map.put("name", "xxx");
map.put("password", "yyy");

Last modified December 22, 2020: clean up website (6e41905afab)