http://code.google.com/p/mybatis/issues/detail?id=43 . Map underscore db columnnames to camelcase properties. New config param "mapUnderscoreToCamelCase" (defaults to false)

Author: emacarron

src/main/java/org/apache/ibatis/builder/xml/XMLConfigBuilder.java

@@ -177,6 +177,7 @@ private void settingsElement(XNode context) throws Exception {
       configuration.setUseGeneratedKeys(booleanValueOf(props.getProperty("useGeneratedKeys"), false));
       configuration.setDefaultExecutorType(ExecutorType.valueOf(stringValueOf(props.getProperty("defaultExecutorType"), "SIMPLE")));
       configuration.setDefaultStatementTimeout(integerValueOf(props.getProperty("defaultStatementTimeout"), null));
+      configuration.setMapUnderscoreToCamelCase(booleanValueOf(props.getProperty("mapUnderscoreToCamelCase"), false));
     }
   }
 

src/main/java/org/apache/ibatis/executor/resultset/FastResultSetHandler.java

@@ -59,6 +59,7 @@ public class Configuration {
 
   protected Environment environment;
 
+  protected boolean mapUnderscoreToCamelCase = false;
   protected boolean lazyLoadingEnabled = false;
   protected boolean aggressiveLazyLoading = true;
   protected boolean multipleResultSetsEnabled = true;
@@ -115,6 +116,14 @@ public Configuration() {
     typeAliasRegistry.registerAlias("WEAK", WeakCache.class.getName());
   }
 
+  public boolean isMapUnderscoreToCamelCase() {
+    return mapUnderscoreToCamelCase;
+  }
+
+  public void setMapUnderscoreToCamelCase(boolean mapUnderscoreToCamelCase) {
+    this.mapUnderscoreToCamelCase = mapUnderscoreToCamelCase;
+  }
+  
   public void addLoadedResource(String resource) {
     loadedResources.add(resource);
   }

src/main/java/org/apache/ibatis/executor/resultset/NestedResultSetHandler.java

@@ -0,0 +1,28 @@
+package org.apache.ibatis.submitted.camelcase;
+
+public class Camel {
+  
+  private String id;
+  private String firstName;
+  private String LAST_NAME;
+  
+  public String getId() {
+    return id;
+  }
+  public void setId(String id) {
+    this.id = id;
+  }
+  public String getFirstName() {
+    return firstName;
+  }
+  public void setFirstName(String firstName) {
+    this.firstName = firstName;
+  } 
+  public String getLAST_NAME() {
+    return LAST_NAME;
+  }
+  public void setLAST_NAME(String last_name) {
+    LAST_NAME = last_name;
+  }
+
+}

src/main/java/org/apache/ibatis/session/Configuration.java

@@ -0,0 +1,62 @@
+package org.apache.ibatis.submitted.camelcase;
+
+import java.io.Reader;
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.util.List;
+import java.util.Map;
+
+import org.apache.ibatis.io.Resources;
+import org.apache.ibatis.jdbc.ScriptRunner;
+import org.apache.ibatis.session.SqlSession;
+import org.apache.ibatis.session.SqlSessionFactory;
+import org.apache.ibatis.session.SqlSessionFactoryBuilder;
+import org.junit.Assert;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+public class CamelCaseMappingTest {
+
+	protected static SqlSessionFactory sqlSessionFactory;
+
+	@BeforeClass
+	public static void setUp() throws Exception {
+		Connection conn = null;
+
+		try {
+			Class.forName("org.hsqldb.jdbcDriver");
+			conn = DriverManager.getConnection("jdbc:hsqldb:mem:gname", "sa", "");
+			Reader reader = Resources.getResourceAsReader("org/apache/ibatis/submitted/camelcase/CreateDB.sql");
+			ScriptRunner runner = new ScriptRunner(conn);
+			runner.setLogWriter(null);
+			runner.setErrorLogWriter(null);
+			runner.runScript(reader);
+			conn.commit();
+			reader.close();
+
+			reader = Resources.getResourceAsReader("org/apache/ibatis/submitted/camelcase/MapperConfig.xml");
+			sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);
+			reader.close();
+
+		} finally {
+			if (conn != null) {
+				conn.close();
+			}
+		}
+	}
+
+	@SuppressWarnings("unchecked")
+	@Test
+	public void testIt() {
+		SqlSession sqlSession = sqlSessionFactory.openSession();
+		try {
+			List<Camel> list = sqlSession.selectList("org.apache.ibatis.submitted.camel.doSelect");
+			Assert.assertTrue(list.size() > 0);
+			Assert.assertNotNull(list.get(0).getFirstName());
+			Assert.assertNull(list.get(0).getLAST_NAME());
+		} finally {
+			sqlSession.close();
+		}
+	}
+
+}

src/test/java/org/apache/ibatis/submitted/camelcase/Camel.java

@@ -0,0 +1,14 @@
+drop table names if exists;
+
+create table names (
+  ID int,
+  FIRST_NAME varchar(20),
+  LAST_NAME varchar(20)
+);
+
+insert into names (ID, FIRST_NAME, LAST_NAME) values(1, 'Fred', 'Flintstone');
+insert into names (ID, FIRST_NAME, LAST_NAME) values(2, 'Wilma', 'Flintstone');
+insert into names (ID, FIRST_NAME, LAST_NAME) values(3, 'Pebbles', 'Flintstone');
+insert into names (ID, FIRST_NAME, LAST_NAME) values(4, 'Barney', 'Rubble');
+insert into names (ID, FIRST_NAME, LAST_NAME) values(5, 'Betty', 'Rubble');
+insert into names (ID, FIRST_NAME, LAST_NAME) values(6, 'Bamm Bamm', 'Rubble');

src/test/java/org/apache/ibatis/submitted/camelcase/CamelCaseMappingTest.java

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE mapper
+    PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
+    "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
+
+<mapper namespace="org.apache.ibatis.submitted.camel">
+
+	<select id="doSelect" resultType="org.apache.ibatis.submitted.camelcase.Camel">
+		select * from names
+	</select>
+
+</mapper>

src/test/java/org/apache/ibatis/submitted/camelcase/CreateDB.sql

@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+
+<!DOCTYPE configuration
+    PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
+    "http://mybatis.org/dtd/mybatis-3-config.dtd">
+
+<configuration>
+
+	<settings>
+		<setting name="mapUnderscoreToCamelCase" value="true" />
+	</settings>
+
+	<environments default="development">
+		<environment id="development">
+			<transactionManager type="JDBC">
+				<property name="" value="" />
+			</transactionManager>
+			<dataSource type="UNPOOLED">
+				<property name="driver" value="org.hsqldb.jdbcDriver" />
+				<property name="url" value="jdbc:hsqldb:mem:gname" />
+				<property name="username" value="sa" />
+			</dataSource>
+		</environment>
+	</environments>
+
+	<mappers>
+		<mapper resource="org/apache/ibatis/submitted/camelcase/Map.xml" />
+	</mappers>
+
+</configuration>