SpringBoot容器-与@AutoWired和没有@AutoWired有什么区别？

Question

也许给出问题的最好方法是在下面显示代码：

public class DBConnection {


    private String Host;
    private String username;
    private String password;

    public DBConnection(String Host, String username, String password)
    {
        this.Host = Host;
        this.username = username;
        this.password = password;
    }

    public void addUser(String name)
    {
        System.out.println("add to db");
    }
}

public class UserService {

    public DBConnection dbConnection;

    public UserService(DBConnection dbConnection){

        this.dbConnection = dbConnection;
    }

    public void register()
    {
        dbConnection.addUser("xd");
    }

}

public class UserService {

    public DBConnection dbConnection;

    @Autowired
    public UserService(DBConnection dbConnection){

        this.dbConnection = dbConnection;
    }

    public void register()
    {
        dbConnection.addUser("xd");
    }

}

Answer 1

Spring将单个构造函数压缩为@autowired。那就没什么区别了。

如果有多个构造函数，那么您必须将其中一个标记为@autowired，以让Spring知道应该使用哪个ctor实例化bean。