java.lang.NoSuchMethodException: java.sql.Date.(java.lang.String)

com.vaadin.data.Property$ConversionException:
    java.lang.NoSuchMethodException:
    java.sql.Date.(java.lang.String)

What is the fix for this... here is my POJO class

package your.intermedix.domain;

import java.io.Serializable;
import java.sql.Date;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;

/**
 * Contact POJO.
 *
 * @hibernate.class table = "contact"
 * @hibernate.cache usage = "read-write"
 */

public class Contact implements Serializable {

    private static final long serialVersionUID = -8361595011677919387L;

    /**
     *
     * @hibernate.id    generator-class = "increment"
     *                  column = "clientid"
     */

    private Long id = null;

    /**
    *
    * @hibernate.property  column = "name"
    *                      length = "100"
    *                      not-null = "true"
    */
    private String name = null;

    /**
    *
    * @hibernate.property  column = "email"
    *                      length = "100"
    *                      not-null = "true"
    */

    private String email;

    /**
    *
    * @hibernate.property  column = "lastname"
    *                      length = "100"
    *                      not-null = "true"
    */
    private String lastname;

    /**
    *
    * @hibernate.property  column = "designation"
    *                      length = "100"
    *                      not-null = "true"
    */
    private String designation;

    /**
    *
    * @hibernate.property  column = "date"
    *                      length = "100"
    *                      not-null = "true"
    */

    private Date date;

    /**
    *
    * @hibernate.property  column = "comments"
    *                      length = "100"
    *                      not-null = "true"
    */

    private String comments;



    public Long getId() {
        return id;
    }

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


    public String getDesignation(){
        return designation;
    }

    public void setDesignation(String designation){
        this.designation = designation;
    }


    public String getEmail(){
        return email;
    }

    public void setEmail(String email){
        this.email = email;
    }


    public String getLastname(){
        return lastname;
    }

    public void setLastname(String lastname){
        this.lastname= lastname;
    }


    public String getName(){
        return name;
    }

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

    public Date getDate(){
        return date;
    }

    public void setDate(Date date){
        this.date = date;
    }

    public String getComments(){
        return comments;
    }

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


    public String toString()
    {
        return "designation = '" + designation + "',email='"+ email +"', lastname='"+ lastname +"', name = '" + name + "', date='" + date +"', comments='" + comments +"'";
    }

}