對於sql欄位非空但插入值為空，將值轉換為空的字串
第一步：實現mybatls中的介面TypeHandler，其中有四個方法
public String getResult(ResultSet arg0, String arg1) throws SQLException
public String getResult(ResultSet arg0, int arg1) throws SQLException
public String getResult(CallableStatement arg0, int arg1) throws SQLException
public void setParameter(PreparedStatement arg0, int arg1, String arg2, JdbcType arg3) throws SQLException
主要用第四個方法。
第二步：建立一個類實現這個介面
package com.rthd.controller.person;
import java.sql.CallableStatement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.TypeHandler;
public class NullValueHandler implements TypeHandler<String> {
@Override
public String getResult(ResultSet arg0, String arg1) throws SQLException {
// TODO Auto-generated method stub
return arg0.getString(arg1);
}
@Override
public String getResult(ResultSet arg0, int arg1) throws SQLException {
// TODO Auto-generated method stub
return arg0.getString(arg1);
}
@Override
public String getResult(CallableStatement arg0, int arg1) throws SQLException {
// TODO Auto-generated method stub
return arg0.getString(arg1);
}
@Override
public void setParameter(PreparedStatement arg0, int arg1, String arg2, JdbcType arg3) throws SQLException {
if(arg2==null && arg3==JdbcType.VARCHAR
arg0.setString(arg1, "");
}else{
arg0.setString(arg1, arg2);
}
}
}
第三步：在spring-mybatils配置檔案中注入
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="typeAliasesPackage" value="com.rthd.bean"></property>
<!-- 插入為空的值是實現介面typeHandlers -->
<property name="typeHandlersPackage" value="com.rthd.controller.person"></property>
第四步：在sql語句中
#{dimiapport,jdbcType=VARCHAR,typeHandler=com.rthd.controller.person.NullValueHandler},
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