事务与批量写入

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package demo.mybatis;
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import org.apache.ibatis.io.Resources;
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import org.apache.ibatis.session.SqlSession;
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import org.apache.ibatis.session.SqlSessionFactory;
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import org.apache.ibatis.session.SqlSessionFactoryBuilder;
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import java.io.InputStream;
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public class TransactionDemo {
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    public static void main(String[] args) throws Exception {
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        try (InputStream in = Resources.getResourceAsStream("mybatis-config.xml")) {
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            SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(in);
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            try (SqlSession session = factory.openSession(false)) {
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                UserMapper mapper = session.getMapper(UserMapper.class);
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                User alice = mapper.selectById(findIdByName(mapper, "alice"));
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                mapper.updateEmail(alice.getId(), "alice.mybatis@example.com");
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                session.commit();
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                System.out.println("commit ok: alice updated");
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            }
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            try (SqlSession session = factory.openSession(false)) {
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                UserMapper mapper = session.getMapper(UserMapper.class);
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                User bob = mapper.selectById(findIdByName(mapper, "bob"));
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                mapper.updateEmail(bob.getId(), "bob.fail@example.com");
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                throw new IllegalStateException("simulate error");
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            } catch (Exception ex) {
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                System.out.println("rollback expected: " + ex.getMessage());
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            }
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            try (SqlSession session = factory.openSession(true)) {
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                UserMapper mapper = session.getMapper(UserMapper.class);
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                User bob = mapper.selectById(findIdByName(mapper, "bob"));
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                System.out.println("bob email still: " + bob.getEmail());
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            }
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        }
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    }
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    private static long findIdByName(UserMapper mapper, String name) {
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        return mapper.search(name, 1).stream()
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                .filter(u -> name.equals(u.getUserName()))
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                .findFirst()
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                .map(User::getId)
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                .orElseThrow();
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    }
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}

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package demo.mybatis;
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import org.apache.ibatis.io.Resources;
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import org.apache.ibatis.session.ExecutorType;
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import org.apache.ibatis.session.SqlSession;
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import org.apache.ibatis.session.SqlSessionFactory;
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import org.apache.ibatis.session.SqlSessionFactoryBuilder;
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import java.io.InputStream;
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public class BatchDemo {
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    public static void main(String[] args) throws Exception {
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        try (InputStream in = Resources.getResourceAsStream("mybatis-config.xml")) {
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            SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(in);
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            try (SqlSession session = factory.openSession(ExecutorType.BATCH, false)) {
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                UserMapper mapper = session.getMapper(UserMapper.class);
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                for (int i = 0; i < 5; i++) {
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                    mapper.insert(new User("batch" + i, "b" + i + "@example.com", 1));
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                }
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                session.flushStatements();
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                session.commit();
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                System.out.println("batch insert committed");
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            }
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        }
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    }
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}