EJB3.0 example

[santhoshkumar samala]

I have created an ejb3.0 entity bean example with @ManytoOne relation. Iam getting a strange error

   Caused by: java.sql.BatchUpdateException: Incorrect integer value: '��' for column 'book' at row 1
at com.mysql.jdbc.PreparedStatement.executeBatchSerially(PreparedStatement.java:1666)
at com.mysql.jdbc.PreparedStatement.executeBatch(PreparedStatement.java:1082)
at org.jboss.resource.adapter.jdbc.WrappedStatement.executeBatch(WrappedStatement.java:519)
at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:48)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:246)
... 36 more
 

my example code is as follows:
Book.java

 package com.ig.example;
 
import java.util.HashSet;
import java.util.Set;
 
import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.OneToMany;
import javax.persistence.OneToOne;
import javax.persistence.SequenceGenerator;
import javax.persistence.Table;
 

@Entity
@Table(name="book")
public class Book implements java.io.Serializable{
 
/**
 * 
 */
private static final long serialVersionUID = 1L;
private Integer id;
private String title;
private Set<Author> authors = new HashSet<Author>(0);

@Id 
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}

@OneToMany(fetch = FetchType.LAZY, cascade = {CascadeType.ALL}, mappedBy = "book")
public Set<Author> getAuthors() {
return authors;
}
public void setAuthors(Set<Author> authors) {
this.authors = authors;
}

public void addAuthor(Author author){
author.setBook(this);
this.authors.add(author);
}

public void removeAuthor(Author author){
authors.remove(author);
}

public Book() {
super();
 }

@Override
public String toString() {
return "Book: " + getId() + " Title " + getTitle();
}



}
 

Author.java

package com.ig.example;
 
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
 
@Entity
@Table(name = "author")
public class Author implements java.io.Serializable{
 
/**
 * 
 */
private static final long serialVersionUID = 1L;
@Id
private int id;
private String name;
private Book book;

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "book", unique = false, nullable = true, insertable = true, updatable = true)
public Book getBook() {
return book;
}
public void setBook(Book book) {
this.book = book;
}
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;
}

}
 

my stateful session bean has following code :

 public void Test() {
Book book = new Book();
book.setId(1);
book.setTitle("santhosh first example");
Author author1 = new Author();
author1.setId(1);
author1.setName("santhosh");
book.addAuthor(author1);
em.persist(book);
}
  

Iam using Mysql, can you please tell me what can be the fix for this?

[santhoshkumar samala]

I was able to solve the above problem..

I have added

 @Id @GeneratedValue   

above getId method of each entity.