hibernate问题,急

Question

<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
          "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
          "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"><!-- Generated by MyEclipse Hibernate Tools.                   -->
<hibernate-configuration> <session-factory>
<property name="connection.username">root</property>
<property name="connection.url">
jdbc:mysql://localhost:3306/Sales
</property>
<property name="dialect">
org.hibernate.dialect.MySQLDialect
</property>
<property name="myeclipse.connection.profile">MySql</property>
<property name="connection.password">ok</property>
<property name="connection.driver_class">
org.gjt.mm.mysql.Driver
</property>
<property name="show_sql">true</property>
<mapping resource="com/fund/to/FinancialAccount.hbm.xml" />
<mapping resource="com/fund/to/Sales.hbm.xml" />
<mapping resource="com/fund/to/Fund.hbm.xml"></mapping> </session-factory></hibernate-configuration>

Answer 1

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- 
    Mapping file autogenerated by MyEclipse Persistence Tools
-->
<hibernate-mapping>
    <class name="com.fund.to.Fund" table="fund" catalog="sales">
        <id name="fundNo" type="java.lang.Integer">
            <column name="FUND_NO" />
            <generator class="increment" />
        </id>
        <property name="fundName" type="java.lang.String">
            <column name="FUND_NAME" length="40" />
        </property>
        <property name="price" type="java.lang.Double">
            <column name="PRICE" precision="10" />
        </property>
        <property name="description" type="java.lang.String">
            <column name="DESCRIPTION" length="100" />
        </property>
        <property name="status" type="java.lang.String">
            <column name="STATUS" length="50" />
        </property>
        <property name="createdDate" type="java.util.Date">
            <column name="CREATED_DATE" length="10" />
        </property>
    </class>
</hibernate-mapping>

Answer 2

java.lang.ClassCastException 
类型转换失败，看你插入数据的时候类型是否正确。

Answer 3

Integer类型我没有插入,是主键自增长的

Answer 4

把自增长主键改为integer且非自增长的看看,

Answer 5

package com.fund.to;import java.util.Date;/**
 * Fund generated by MyEclipse Persistence Tools
 */public class Fund implements java.io.Serializable { // Fields private Integer fundNo; private String fundName; private Double price; private String description; private String status; private Date createdDate; // Constructors /** default constructor */
public Fund() {
} /** full constructor */
public Fund(String fundName, Double price, String description,
String status, Date createdDate) {
this.fundName = fundName;
this.price = price;
this.description = description;
this.status = status;
this.createdDate = createdDate;
} // Property accessors public Integer getFundNo() {
return this.fundNo;
} public void setFundNo(Integer fundNo) {
this.fundNo = fundNo;
} public String getFundName() {
return this.fundName;
} public void setFundName(String fundName) {
this.fundName = fundName;
} public Double getPrice() {
return this.price;
} public void setPrice(Double price) {
this.price = price;
} public String getDescription() {
return this.description;
} public void setDescription(String description) {
this.description = description;
} public String getStatus() {
return this.status;
} public void setStatus(String status) {
this.status = status;
} public Date getCreatedDate() {
return this.createdDate;
} public void setCreatedDate(Date createdDate) {
this.createdDate = createdDate;
}}

Answer 6

<generator class="increment" />改为 <generator class="identity" />

Answer 7

已经解决第一个问题,是我的返回值的问题
第二个已经找到原因,是在生成映射文件的时候
<property name="price" type="java.lang.Double">
  <column name="PRICE" precision="10" />
</property>
这个出了问题,不知道怎么解决
这个属性在mysql数据库里是decimal(10,2)类型

Answer 8

<property name="price" type="java.lang.Double">
  <column name="PRICE" length="10" />
</property>

Answer 9

第二个问题也已经解决是mysql驱动的BUG,我用的是3.2的,换个5.0的就搞定了