org.springframework.orm.hibernate3.HibernateSystemException: ... why it was?

Hi i am using Spring-Hibernate with HibernateDaoSupport, where my Dao was extends by HibernateDaoSupport. when i am getting the data from table the following error was raising, when i am submitting the data on same table it running successfuly.. can any one give your idea?

Error:

org.springfram开发者_运维百科ework.orm.hibernate3.HibernateSystemException: Null value was assigned to a property of primitive type setter of com.mypack.table.TblValues.minval; nested exception is org.hibernate.PropertyAccessException: Null value was assigned to a property of primitive type setter of com.mypack.table.TblValues.minval

Note: minval is the one of the column in table TblValues, and i assigning null value.

code in table pojo for getter & setter property:

@Column(name="minVal",nullable=true)
    public byte getMinVal() {
        return this.minVal;
    }
public void setMinVal(byte minVal) {
        this.minVal = minVal;
    }

You can't have a nullable primitive type, that's a contradiction (in Java, at least).

If you want minVal to be nullable, you need to use the Byte java type, not byte.