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POMyBatis select statement returns null values
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I'm trying to run a simple MyBatis example, selecting all rows from the "trains" table. The problem is that the query performs, but it returns a list with the correct number of elements, but populated with null values. The same query runned directly with JDBC PreparedStatement works fine. Perhaps it's a configuration problem, but I cannot figure out what I'm doing wrong. Here is the code. Thanks in advance. Train.java <pre><code>package org.example.mybatis.domain; public class Train implements Serializable { private int id; private String type; // getters and setters } </code></pre> TrainMapper.java <pre><code>package org.example.mybatis.persistence; public interface TrainMapper { List<Train> getAllTrains(); } </code></pre> TrainSelector.java <pre><code>package org.example.mybatis.test; public class TrainSelector implements TrainMapper { private static String resource = "mybatis-config.xml"; private static SqlSessionFactory factory = null; private SqlSessionFactory getSqlSessionFactory() { if (factory == null) { try { InputStream inputStream = Resources.getResourceAsStream(resource); factory = new SqlSessionFactoryBuilder().build(inputStream); } catch (IOException e) { e.printStackTrace(); } } return factory; } @Override public List<Train> getAllTrains() { List<Train> trains = null; SqlSession session = getSqlSessionFactory().openSession(); try { TrainMapper mapper = session.getMapper(TrainMapper.class); trains = mapper.getAllTrains(); } finally { session.close(); } return trains; } public static void main(String[] args) { List<Train> trains = null; TrainSelector trainSelector = new TrainSelector(); trains = trainSelector.getAllTrains(); System.out.println(trains); } } </code></pre> mybatis-config.xml <pre><code><?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> <properties resource="database.properties" /> <typeAliases> <typeAlias alias="Train" type="org.example.mybatis.domain.Train" />  </typeAliases> <environments default="development"> <environment id="development"> <transactionManager type="JDBC" /> <dataSource type="POOLED"> <property name="driver" value="${database.driver}" /> <property name="url" value="${database.url}" /> <property name="username" value="${database.username}" /> <property name="password" value="${database.password}" /> </dataSource> </environment> </environments> <mappers> <mapper resource="org/example/mybatis/persistence/TrainMapper.xml" /> </mappers> </configuration> </code></pre> TrainMapper.xml <pre><code><?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.example.mybatis.persistence.TrainMapper"> <cache /> <select id="getAllTrains" parameterType="list" resultType="Train"> SELECT * FROM trains </select> </mapper> </code></pre> JdbcStatementExample.java <pre><code>package org.example.mybatis.test; public class JdbcStatementExample { private static void selectAllTrains() throws SQLException { String sql = "SELECT * FROM trains"; Connection conn = null; PreparedStatement ps = null; ResultSet rs = null; String url = "jdbc:mysql://localhost/testing"; String user = "test"; String password = "test"; try { conn = DriverManager.getConnection(url, user, password); ps = conn.prepareStatement(sql); rs = ps.executeQuery(); while (rs.next()) { String id = rs.getString("train_id"); String type = rs.getString("train_type"); System.out.println("id: " + id); System.out.println("type: " + type); } } catch (SQLException e) { throw new RuntimeException(e); } finally { if (ps != null) { ps.close(); } if (conn != null) { conn.close(); } } } public static void main(String[] args) { try { selectAllTrains(); } catch (SQLException e) { e.printStackTrace(); } } } </code></pre>
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MyBatis select statement returns null values
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A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.