Hibernate 运行时异常：以未映射类为目标使用@OneToMany或@ManyToMany

请问sombody能帮我吗？？在Client.class中保存数据时出现此错误

package com.pojo;

import java.io.Serializable;
import java.util.List;
import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.OneToMany;

@Entity
public class Client implements Serializable {
private String Name;
private String Address;
private float balance;
@Id
@GeneratedValue
private int client_id;

@OneToMany(targetEntity=Ledger.class,mappedBy="client",cascade= CascadeType.ALL,fetch= FetchType.EAGER)
private List<Ledger> ledger;

public float getBalance() {
    return balance;
}

public void setBalance(float balance) {
    this.balance = balance;
}

public List<Ledger> getLedger() {
    return ledger;
}

public void setLedger(List<Ledger> ledger) {
    this.ledger = ledger;
}

public String getAddress() {
    return Address;
}

public void setAddress(String Address) {
    this.Address = Address;
}

public String getName() {
    return Name;
}

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

public int getClient_id() {
    return client_id;
}

public void setClient_id(int client_id) {
    this.client_id = client_id;
}

}    

Client.class

package com.pojo;

import java.io.Serializable;
import java.util.List;
import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.OneToMany;

@Entity
public class Client implements Serializable {
private String Name;
private String Address;
private float balance;
@Id
@GeneratedValue
private int client_id;

@OneToMany(targetEntity=Ledger.class,mappedBy="client",cascade= CascadeType.ALL,fetch= FetchType.EAGER)
private List<Ledger> ledger;

public float getBalance() {
    return balance;
}

public void setBalance(float balance) {
    this.balance = balance;
}

public List<Ledger> getLedger() {
    return ledger;
}

public void setLedger(List<Ledger> ledger) {
    this.ledger = ledger;
}

public String getAddress() {
    return Address;
}

public void setAddress(String Address) {
    this.Address = Address;
}

public String getName() {
    return Name;
}

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

public int getClient_id() {
    return client_id;
}

public void setClient_id(int client_id) {
    this.client_id = client_id;
}

}    

它正在显示此错误

org.hibernate.AnnotationException: Use of @OneToMany or @ManyToMany targeting an unmapped class: com.pojo.Client.ledger[com.pojo.Ledger]

请有人帮帮我：（

你忘了添加

ac.addAnnotatedClass（Ledger.class）；

到您的Hibernate配置

以及购买的数量

---

无论如何，您不想为每个servlet调用创建一个

SessionFactory

，

thanx alot orid..i jst gt 2知道这一点..但是我遇到了另一个错误..org.hibernate.hibernate异常：无法同时获取多个包您必须显示完整的跟踪。这基本上意味着您在同一个类中有两个列表在一个映射实体中，用“@OneToMany（…fetch=FetchType.EAGER…）注释的。Hibernate不支持此操作

org.hibernate.AnnotationException: Use of @OneToMany or @ManyToMany targeting an unmapped class: com.pojo.Client.ledger[com.pojo.Ledger]