插入代码，为什么没有行号？？？？？

出入代码，为什么没有行号呢？？？？？？public class User implements Serializable{
private int id;
private String name;
private String sex;

public User() {
}

public User(int id, String name, String sex) {
this.id = id;
this.name = name;
this.sex = sex;
}

public int getId() {
return id;
}

public void setId(int id) {
this.id = id;
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public String getSex() {
return sex;
}

public void setSex(String sex) {
this.sex = sex;
}

@Override
public String toString() {
return "User{" +
"id=" + id +
", name='" + name + '\'' +
", sex='" + sex + '\'' +
'}';
}
}

public class User implements Serializable{
private int id;
private String name;
private String sex;

public User() {
}

public User(int id, String name, String sex) {
this.id = id;
this.name = name;
this.sex = sex;
}

public int getId() {
return id;
}

public void setId(int id) {
this.id = id;
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public String getSex() {
return sex;
}

public void setSex(String sex) {
this.sex = sex;
}

@Override
public String toString() {
return "User{" +
"id=" + id +
", name='" + name + '\'' +
", sex='" + sex + '\'' +
'}';
}
}