[Java][DB] DerbyのTRANSACTION_READ_COMMITTEDはSELECTで待たされる

data.xml

<?xml version="1.0" encoding="UTF-8"?>
<dataset>
  <sample id="1" name="name1" />
</dataset>

DatabaseLockReadTest.java

/**
 * Derbyでは更新中の行をTRANSACTION_READ_COMMITTEDでSELECTしたときに待ちが発生する.
 * OracleやMySQLでは待たずに更新前の情報を取得するので違う動作。DB2はDerbyと同じ？
 */
public class DatabaseLockReadTest {
  private Connection lockedConn;

  @Before
  public void setUp() throws Exception {
    setLocksWaitTimeout();
    lockedConn = getConnection();
    lockedConn.setAutoCommit(false);
    updateNotCommit();
  }

  @After
  public void tearDown() throws Exception {
    lockedConn.rollback();
    lockedConn.close();
  }

  @Test
  public void testReadCommitted() {
    try {
      String name = selectLockedRow(Connection.TRANSACTION_READ_COMMITTED);

      fail(name);
    } catch (SQLException e) {
      assertThat(e.getSQLState(), is("40XL1"));
    }
  }

  @Test
  public void testReadUncommitted() throws SQLException {
    String name = selectLockedRow(Connection.TRANSACTION_READ_UNCOMMITTED);

    assertThat(name, is("updated"));
  }

  private void setLocksWaitTimeout() throws SQLException {
    try (Connection conn = getConnection();
        Statement stmt = conn.createStatement()) {
      stmt.execute("CALL SYSCS_UTIL.SYSCS_SET_DATABASE_PROPERTY('derby.locks.waitTimeout', '1')");
    }
  }

  private void updateNotCommit() throws SQLException {
    PreparedStatement stmt = lockedConn.prepareStatement("UPDATE sample SET name='updated' WHERE id=1");
    stmt.execute();
  }

  private String selectLockedRow(int isolationLevel) throws SQLException {
    try (Connection conn = getConnection()) {
      conn.setTransactionIsolation(isolationLevel);
      ResultSet rs = conn.createStatement().executeQuery("SELECT name FROM sample WHERE id=1");
      rs.next();
      return rs.getString("name");
    }
  }

  private Connection getConnection() throws SQLException {
    return DriverManager.getConnection("jdbc:derby:data/derby/sample");
  }
}