java.lang.StackOverflowError: null
The reason for the error is a stack overflow.
It is due to an infinite loop or infinite recursion when using Jpa query.
For example, the following two bidirectionally related entity columns:
public class User{
//Other properties and get set methods are omitted
@ManyToMany
@JoinTable(name = "UserRole", joinColumns = { @JoinColumn(name = "userId") }, inverseJoinColumns ={@JoinColumn(name = "roleId") })
private List<Role> roleList;
}
--------
public class Role{
//Other properties are ignored by the get set method
@ManyToMany
@JoinTable(name = "UserRole", joinColumns = { @JoinColumn(name = "roleId") }, inverseJoinColumns ={@JoinColumn(name = "userId") })
private List<Role> userList;
}
When traversing the collection,
for （Role role: user.getRoleList ()） {
System.out.println(role);
}
When a role object is output, the userlist is also output. Because it is bidirectionally associated, the user object is also triggered, followed by the roleList. . . Generate infinite recursion, resulting in stack overflow.
The solution is:
for （Role role: user.getRoleList ()） {
role.setUserList(null);//Terminate early so that infinite recursion will not occur
System.out.println(role);
}