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POjpa entity relation many to many self relation
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  1. POjpa entity relation many to many self relation
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    copied!<p>I wish to make jpa entity for clients, something like adding friends on facebook or googe+ Got a bit confused </p> <p><img src="https://i.stack.imgur.com/aTaG9.png" alt="enter image description here"></p> <pre><code>This auto generates to code below, /* * To change this template, choose Tools | Templates * and open the template in the editor. */ package entities; import java.io.Serializable; import java.util.List; import javax.persistence.Basic; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.JoinColumn; import javax.persistence.JoinTable; import javax.persistence.ManyToMany; import javax.persistence.NamedQueries; import javax.persistence.NamedQuery; import javax.persistence.Table; import javax.validation.constraints.NotNull; import javax.validation.constraints.Size; import javax.xml.bind.annotation.XmlRootElement; import javax.xml.bind.annotation.XmlTransient; /** * * @author nikola */ @Entity @Table(name = "Client") @XmlRootElement @NamedQueries({ @NamedQuery(name = "Client.findAll", query = "SELECT c FROM Client c"), @NamedQuery(name = "Client.findByClientId", query = "SELECT c FROM Client c WHERE c.clientId = :clientId"), @NamedQuery(name = "Client.findByClientName", query = "SELECT c FROM Client c WHERE c.clientName = :clientName")}) public class Client implements Serializable { private static final long serialVersionUID = 1L; @Id @Basic(optional = false) @NotNull @Column(name = "ClientId") private Integer clientId; @Size(max = 45) @Column(name = "ClientName") private String clientName; @JoinTable(name = "Friends", joinColumns = { @JoinColumn(name = "Client_ClientId", referencedColumnName = "ClientId")}, inverseJoinColumns = { @JoinColumn(name = "Client_ClientId1", referencedColumnName = "ClientId")}) @ManyToMany private List&lt;Client&gt; clientList; @ManyToMany(mappedBy = "clientList") private List&lt;Client&gt; clientList1; public Client() { } public Client(Integer clientId) { this.clientId = clientId; } public Integer getClientId() { return clientId; } public void setClientId(Integer clientId) { this.clientId = clientId; } public String getClientName() { return clientName; } public void setClientName(String clientName) { this.clientName = clientName; } @XmlTransient public List&lt;Client&gt; getClientList() { return clientList; } public void setClientList(List&lt;Client&gt; clientList) { this.clientList = clientList; } @XmlTransient public List&lt;Client&gt; getClientList1() { return clientList1; } public void setClientList1(List&lt;Client&gt; clientList1) { this.clientList1 = clientList1; } @Override public int hashCode() { int hash = 0; hash += (clientId != null ? clientId.hashCode() : 0); return hash; } @Override public boolean equals(Object object) { // TODO: Warning - this method won't work in the case the id fields are not set if (!(object instanceof Client)) { return false; } Client other = (Client) object; if ((this.clientId == null &amp;&amp; other.clientId != null) || (this.clientId != null &amp;&amp; !this.clientId.equals(other.clientId))) { return false; } return true; } @Override public String toString() { return "entities.Client[ clientId=" + clientId + " ]"; } } </code></pre> <p>I have clientList and clientList1, do not know which one to use when i wish to add a client to my list of friends. Thanks for any advice.</p>
 

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