Re: abstract property

Kenny Pearce Thu, 13 Sep 2007 06:44:27 -0700

Alright, this is pretty long, but I've developed a basic case for theproblem I'm having, and all the files, output, etc. are copied below.Maybe you can explain what I'm doing wrong.


=============== table create statement =====================

create table my_table (foo varchar(20), bar varchar(20), sub_barvarchar(20));


=============== insert statement ====================
insert into my_table values ('foo', 'bar', 'sub_bar');

=============== config.properties ==================
JDBC.Driver=com.mysql.jdbc.Driver
JDBC.ConnectionURL=jdbc:mysql://localhost:3306/ibatis_test
JDBC.Username=root
JDBC.Password=root

=============== config.xml ================
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE sqlMapConfig
   PUBLIC "-//iBATIS.com//DTD SQL Map Config 2.0//EN"
   "http://www.ibatis.com/dtd/sql-map-config-2.dtd";>

<sqlMapConfig>
   <properties resource="sqlmapconfig/config.properties"/>

      <transactionManager type="JDBC">
      <dataSource type="SIMPLE">

<property name="JDBC.Driver" value="${JDBC.Driver}"/><property name="JDBC.ConnectionURL"value="${JDBC.ConnectionURL}" /><property name="JDBC.Username" value="${JDBC.Username}"/><property name="JDBC.Password" value="${JDBC.Password}"/>

      </dataSource>
   </transactionManager>

   <sqlMap resource="sqlmapconfig/Foo.xml"/>
</sqlMapConfig>

================ Foo.xml ================
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE sqlMap
    PUBLIC "-//iBATIS.com//DTD SQL Map 2.0//EN"
    "http://www.ibatis.com/dtd/sql-map-2.dtd";>


<sqlMap namespace="Foo">
        <resultMap class="Foo" id="fooResultMap">
                <result property="fooString" column="foo"/>
                <result property="myBar" resultMap="Foo.barResultMap"/>
        </resultMap>
        <resultMap class="SubBar" id="barResultMap">
                <result property="barString" column="bar"/>
                <result property="subBarString" column="sub_bar"/>
        </resultMap>
        
        <select id="fooSelect" parameterClass="string" resultClass="Foo"
                        resultMap="fooResultMap">
                SELECT foo, bar, sub_bar from my_table WHERE foo = #value#
        </select>
</sqlMap>

========================== Foo.java ========================
public class Foo {
        private String fooString;
        private Bar myBar;
        
        public String getFooString() {
                return fooString;
        }
        public void setFooString(String fooString) {
                this.fooString = fooString;
        }
        public Bar getMyBar() {
                return myBar;
        }
        public void setMyBar(Bar myBar) {
                this.myBar = myBar;
        }
}

===================== Bar.java ====================
public abstract class Bar {
        private String barString;

        public String getBarString() {
                return barString;
        }

        public void setBarString(String barString) {
                this.barString = barString;
        }
}

=================== SubBar.java =======================
public class SubBar extends Bar {
        private String subBarString;

        public String getSubBarString() {
                return subBarString;
        }

        public void setSubBarString(String subBarString) {
                this.subBarString = subBarString;
        }
}

==================== SQLTest.java ================
import java.io.InputStreamReader;
import java.io.Reader;

import com.ibatis.sqlmap.client.SqlMapClient;
import com.ibatis.sqlmap.client.SqlMapClientBuilder;


public class SQLTest {
        /**
         * @param args
         */
        public static void main(String[] args) {
                SqlMapClient sql = null;
                try
                {

Reader reader = newInputStreamReader(SQLTest.class.getResourceAsStream("/sqlmapconfig/config.xml"));

                        sql = SqlMapClientBuilder.buildSqlMapClient(reader);
                }
                catch (Throwable t)
                {
                        t.printStackTrace();
                        System.exit(1);
                }
                
                Foo myFoo = null;
                try{
                        myFoo = (Foo)sql.queryForObject("fooSelect", "foo");
                }catch(Throwable t){
                        t.printStackTrace();
                        System.exit(2);
                }

System.out.println(myFoo.getFooString() + " - " +myFoo.getMyBar().getBarString()

                                + " - " + 
((SubBar)myFoo.getMyBar()).getSubBarString());
        }
}

=============================================================

Executing SQLTest results in the following being printed to stderr:

com.ibatis.common.jdbc.exception.NestedSQLException:
--- The error occurred in sqlmapconfig/Foo.xml.
--- The error occurred while applying a result map.
--- Check the Foo.fooResultMap.
--- The error happened while setting a property on the result object.

--- Cause: com.ibatis.sqlmap.client.SqlMapException: Error instantiatingcollection property for mapping 'myBar'. Cause:java.lang.InstantiationException

Caused by: java.lang.InstantiationException

Caused by: com.ibatis.sqlmap.client.SqlMapException: Error instantiatingcollection property for mapping 'myBar'. Cause:java.lang.InstantiationException

Caused by: java.lang.InstantiationException

atcom.ibatis.sqlmap.engine.mapping.statement.GeneralStatement.executeQueryWithCallback(GeneralStatement.java:188)atcom.ibatis.sqlmap.engine.mapping.statement.GeneralStatement.executeQueryForObject(GeneralStatement.java:104)atcom.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForObject(SqlMapExecutorDelegate.java:561)atcom.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForObject(SqlMapExecutorDelegate.java:536)atcom.ibatis.sqlmap.engine.impl.SqlMapSessionImpl.queryForObject(SqlMapSessionImpl.java:93)atcom.ibatis.sqlmap.engine.impl.SqlMapClientImpl.queryForObject(SqlMapClientImpl.java:70)

        at SQLTest.main(SQLTest.java:27)

Caused by: com.ibatis.sqlmap.client.SqlMapException: Error instantiatingcollection property for mapping 'myBar'. Cause:java.lang.InstantiationException

Caused by: java.lang.InstantiationException

        ... 6 more
Caused by: java.lang.InstantiationException

atsun.reflect.InstantiationExceptionConstructorAccessorImpl.newInstance(InstantiationExceptionConstructorAccessorImpl.java:30)

        at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
        at java.lang.Class.newInstance0(Class.java:355)
        at java.lang.Class.newInstance(Class.java:308)

atcom.ibatis.sqlmap.engine.mapping.result.BasicResultMap.setNestedResultMappingValue(BasicResultMap.java:395)

        ... 13 more

Caused by:

com.ibatis.sqlmap.client.SqlMapException: Error instantiating collectionproperty for mapping 'myBar'. Cause: java.lang.InstantiationException

Caused by: java.lang.InstantiationException

atcom.ibatis.sqlmap.engine.mapping.result.BasicResultMap.setNestedResultMappingValue(BasicResultMap.java:397)atcom.ibatis.sqlmap.engine.mapping.result.BasicResultMap.applyNestedResultMap(BasicResultMap.java:369)atcom.ibatis.sqlmap.engine.mapping.result.BasicResultMap.setResultObjectValues(BasicResultMap.java:355)atcom.ibatis.sqlmap.engine.mapping.statement.RowHandlerCallback.handleResultObject(RowHandlerCallback.java:63)atcom.ibatis.sqlmap.engine.execution.SqlExecutor.handleResults(SqlExecutor.java:395)atcom.ibatis.sqlmap.engine.execution.SqlExecutor.executeQuery(SqlExecutor.java:185)atcom.ibatis.sqlmap.engine.mapping.statement.GeneralStatement.sqlExecuteQuery(GeneralStatement.java:205)atcom.ibatis.sqlmap.engine.mapping.statement.GeneralStatement.executeQueryWithCallback(GeneralStatement.java:173)atcom.ibatis.sqlmap.engine.mapping.statement.GeneralStatement.executeQueryForObject(GeneralStatement.java:104)atcom.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForObject(SqlMapExecutorDelegate.java:561)atcom.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForObject(SqlMapExecutorDelegate.java:536)atcom.ibatis.sqlmap.engine.impl.SqlMapSessionImpl.queryForObject(SqlMapSessionImpl.java:93)atcom.ibatis.sqlmap.engine.impl.SqlMapClientImpl.queryForObject(SqlMapClientImpl.java:70)

        at SQLTest.main(SQLTest.java:27)
Caused by: java.lang.InstantiationException

atsun.reflect.InstantiationExceptionConstructorAccessorImpl.newInstance(InstantiationExceptionConstructorAccessorImpl.java:30)

        at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
        at java.lang.Class.newInstance0(Class.java:355)
        at java.lang.Class.newInstance(Class.java:308)

atcom.ibatis.sqlmap.engine.mapping.result.BasicResultMap.setNestedResultMappingValue(BasicResultMap.java:395)

        ... 13 more

Caused by:
java.lang.InstantiationException

atsun.reflect.InstantiationExceptionConstructorAccessorImpl.newInstance(InstantiationExceptionConstructorAccessorImpl.java:30)

        at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
        at java.lang.Class.newInstance0(Class.java:355)
        at java.lang.Class.newInstance(Class.java:308)

atcom.ibatis.sqlmap.engine.mapping.result.BasicResultMap.setNestedResultMappingValue(BasicResultMap.java:395)atcom.ibatis.sqlmap.engine.mapping.result.BasicResultMap.applyNestedResultMap(BasicResultMap.java:369)atcom.ibatis.sqlmap.engine.mapping.result.BasicResultMap.setResultObjectValues(BasicResultMap.java:355)atcom.ibatis.sqlmap.engine.mapping.statement.RowHandlerCallback.handleResultObject(RowHandlerCallback.java:63)atcom.ibatis.sqlmap.engine.execution.SqlExecutor.handleResults(SqlExecutor.java:395)atcom.ibatis.sqlmap.engine.execution.SqlExecutor.executeQuery(SqlExecutor.java:185)atcom.ibatis.sqlmap.engine.mapping.statement.GeneralStatement.sqlExecuteQuery(GeneralStatement.java:205)atcom.ibatis.sqlmap.engine.mapping.statement.GeneralStatement.executeQueryWithCallback(GeneralStatement.java:173)atcom.ibatis.sqlmap.engine.mapping.statement.GeneralStatement.executeQueryForObject(GeneralStatement.java:104)atcom.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForObject(SqlMapExecutorDelegate.java:561)atcom.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForObject(SqlMapExecutorDelegate.java:536)atcom.ibatis.sqlmap.engine.impl.SqlMapSessionImpl.queryForObject(SqlMapSessionImpl.java:93)atcom.ibatis.sqlmap.engine.impl.SqlMapClientImpl.queryForObject(SqlMapClientImpl.java:70)

        at SQLTest.main(SQLTest.java:27)

Caused by:

com.ibatis.sqlmap.client.SqlMapException: Error instantiating collectionproperty for mapping 'myBar'. Cause: java.lang.InstantiationException

Caused by: java.lang.InstantiationException

        at SQLTest.main(SQLTest.java:27)
Caused by: java.lang.InstantiationException

atsun.reflect.InstantiationExceptionConstructorAccessorImpl.newInstance(InstantiationExceptionConstructorAccessorImpl.java:30)

        at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
        at java.lang.Class.newInstance0(Class.java:355)
        at java.lang.Class.newInstance(Class.java:308)

atcom.ibatis.sqlmap.engine.mapping.result.BasicResultMap.setNestedResultMappingValue(BasicResultMap.java:395)

        ... 13 more

Caused by:
java.lang.InstantiationException

atsun.reflect.InstantiationExceptionConstructorAccessorImpl.newInstance(InstantiationExceptionConstructorAccessorImpl.java:30)

        at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
        at java.lang.Class.newInstance0(Class.java:355)
        at java.lang.Class.newInstance(Class.java:308)

        at SQLTest.main(SQLTest.java:27)

Caused by:
java.lang.InstantiationException

atsun.reflect.InstantiationExceptionConstructorAccessorImpl.newInstance(InstantiationExceptionConstructorAccessorImpl.java:30)

        at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
        at java.lang.Class.newInstance0(Class.java:355)
        at java.lang.Class.newInstance(Class.java:308)

        at SQLTest.main(SQLTest.java:27)


Niels Beekman wrote:

How could iBATIS throw an InstantiationException when you're not even
telling it the name of your abstract class? Please post the full
exception stacktrace and your result maps.

Niels

-----Original Message-----
From: Kenny Pearce [mailto:[EMAIL PROTECTED]Sent: woensdag 12 september 2007 20:46
To: user-java@ibatis.apache.org
Subject: abstract property

Hello,  
        I am trying to use iBatis in a case where I have an object
hierarchylike the following:
class Foo{
    String fooString;
    Bar myBar;
    //getters and setters omitted
}

abstract class Bar{
    String barString;
    //getters and setters omitted
}

class SubBar extends Bar{
    String subBarString;
    //getters and setters omitted
}

I would like to be able to do this:

<resultMap id="fooResultMap" class="Foo">
    <result property="fooString" column="foo"/>
    <result property="myBar" resultMap="barResultMap"/>
</resultMap>

<resultMap id="barResultMap" class="SubBar">
    <result property="barString" column="bar"/>
    <result proprty="subBarString" column="sub_bar"/>
</resultMap>
<select id="fooSelect" parameterClass="string" resultClass="Foo"resultMap="fooResultMap">
    SELECT foo, bar, sub_bar FROM table WHERE foo = #value#
</select>
But that gives an InstantiationException (despite the fact that thebarResultMap has the class SubBar, which is concrete, specified). Next I
tried using a discriminator and making a separate barResultMap andsubBarResultMap (where subBarResultMap extends barResultMap) with<subMap value="*" ...> on a column that is never null (I'm not sure ifwildcard is supported - I couldn't find discriminator in the docs, butit's not listed on the undocumented features page). That still threw anexception. Next, I changed the select statement to (the equivalent of):
    SELECT foo, bar, sub_bar, 1 as use_submap FROM table WHERE foo =
#value#

and used:

<discriminator column="use_submap" javaType="int">
        <subMap value="1" resultMap="subBarResultMap"/>
</discriminator>

But no go there either.

Is there any way to do this, short of creating a custom object factory?

        Thanks,


--
Kenny Pearce
Hx Technologies

Re: abstract property

Reply via email to