package com.mysema.query.mongodb.domain;

import org.bson.types.ObjectId;
import org.mongodb.morphia.annotations.Entity;
import org.mongodb.morphia.annotations.Id;

import java.util.Date;

@Entity
public class Dates {

    private @Id ObjectId id;

    private Date date;

    public ObjectId getId() {
        return id;
    }

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

    public Date getDate() {
        return date;
    }

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

package com.mysema.query.mongodb.domain;

import java.util.Date;

import org.bson.types.ObjectId;
import org.mongodb.morphia.annotations.Entity;
import org.mongodb.morphia.annotations.Id;

@Entity
public class Dates {

    private @Id ObjectId id;

    private Date date;

    public ObjectId getId() {
        return id;
    }

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

    public Date getDate() {
        return date;
    }

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

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + ((id == null) ? 0 : id.hashCode());
        return result;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (getClass() != obj.getClass())
            return false;
        Dates other = (Dates) obj;
        if (id == null) {
            if (other.id != null)
                return false;
        } else if (!id.equals(other.id))
            return false;
        return true;
    }
}

Add equals and hashCode