Hướng dẫn và ví dụ Spring JDBC

Modal Classes
JdbcTemplate.queryForList -> List
JdbcTemplate.queryForList -> List<Map>
JdbcTemplate.queryForRowSet
JdbcTemplate.query & RowMapper
JdbcTemplate.query & RowCallbackHandler
JdbcTemplate.query & ResultSetExtractor
JdbcTemplate.queryForObject
TODO ..

Trong bài học này tôi sẽ hướng dẫn bạn sử dụng lớp JdbcTemplate, đây là một lớp trung tâm trong Spring JDBC, nó bao gồm các logic phổ biến nhất trong việc sử dụng JDBC API để truy cập vào cơ sở dữ liệu, chẳng hạn như tạo kết nối, tạo các lệnh truy vấn, xóa, sửa, cập nhập dữ liệu... Lớp này có thể tìm thấy trong gói (package) org.springframework.jdbc.core.

Mục tiêu của bài học là cung cấp các vi dụ sử dụng các phương thức của lớp JdbcTemplate.

JdbcTemplate.queryForList
JdbcTemplate.queryForRowSet
JdbcTemplate.query
JdbcTemplate.queryForObject
...

Hãy đảm bảo rằng bạn đã có thể tạo được một project sử dụng Spring JDBC để kết nối vào một cơ sở dữ liệu cụ thể, nếu không bạn có thể tham khảo bài học dưới đây:
Hướng dẫn sử dụng Spring Boot, Spring JDBC và Spring Transaction

1. Modal Classes

Department.java

package org.o7planning.springjdbc.model;

public class Department {

    private Long deptId;
    private String deptNo;
    private String deptName;

    public Department() {

    }

    public Department(Long deptId, String deptNo, String deptName) {
        this.deptId = deptId;
        this.deptNo = deptNo;
        this.deptName = deptName;
    }

    public Long getDeptId() {
        return deptId;
    }

    public void setDeptId(Long deptId) {
        this.deptId = deptId;
    }

    public String getDeptNo() {
        return deptNo;
    }

    public void setDeptNo(String deptNo) {
        this.deptNo = deptNo;
    }

    public String getDeptName() {
        return deptName;
    }

    public void setDeptName(String deptName) {
        this.deptName = deptName;
    }
    
    
}

2. JdbcTemplate.queryForList -> List

Ví dụ đầu tiên và đơn giản nhất với Spring JDBC là việc query lấy ra danh sách các giá trị của một cột.

QueryForListReturnListDAO.java

package org.o7planning.springjdbc.dao;

import java.util.List;

import javax.sql.DataSource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.support.JdbcDaoSupport;
import org.springframework.stereotype.Repository;

@Repository
public class QueryForListReturnListDAO extends JdbcDaoSupport {

    @Autowired
    public QueryForListReturnListDAO(DataSource dataSource) {
        this.setDataSource(dataSource);
    }


    public List<String> getDeptNames() {

        String sql = "Select d.dept_name from Department d ";

        // queryForList(String sql, Class<T> elementType)
        List<String> list = this.getJdbcTemplate().queryForList(sql, String.class);

        return list;
    }

    public List<String> getDeptNames(String searchName) {

        String sql = "Select d.dept_name from Department d "//
                + " Where d.dept_name like ? ";

        // queryForList(String sql, Class<T> elementType, Object... args)
        List<String> list = this.getJdbcTemplate().queryForList(sql, String.class, //
                "%" + searchName + "%");

        return list;
    }


}

QueryForListReturnList_Test.java

package org.o7planning.springjdbc.demo;

import java.sql.SQLException;
import java.util.List;

import org.o7planning.springjdbc.config.AppConfiguration;
import org.o7planning.springjdbc.dao.QueryForListReturnListDAO;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class QueryForListReturnList_Test {

    public static void main(String[] args) throws SQLException {

        ApplicationContext context = new AnnotationConfigApplicationContext(AppConfiguration.class);

        QueryForListReturnListDAO dao = context.getBean(QueryForListReturnListDAO.class);

        List<String> names = dao.getDeptNames("A");

        for (String name : names) {

            System.out.println("Dept Name: " + name);
        }
    }

}

Chạy ví dụ:

Dept Name: ACCOUNTING
Dept Name: RESEARCH
Dept Name: SALES
Dept Name: OPERATIONS

3. JdbcTemplate.queryForList -> List<Map>

// JdbcTemplate.queryForList methods, return List<Map<String,Object>>

public List<Map<String, Object>> queryForList(String sql,
               Object[] args, int[] argTypes) throws DataAccessException;


public List<Map<String, Object>> queryForList(String sql,
               Object... args) throws DataAccessException;

Ví dụ:

QueryForListReturnListMapDAO.java

package org.o7planning.springjdbc.dao;

import java.sql.Types;
import java.util.Calendar;
import java.util.Date;
import java.util.List;
import java.util.Map;

import javax.sql.DataSource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.support.JdbcDaoSupport;
import org.springframework.stereotype.Repository;

@Repository
public class QueryForListReturnListMapDAO extends JdbcDaoSupport {

    @Autowired
    public QueryForListReturnListMapDAO(DataSource dataSource) {
        this.setDataSource(dataSource);
    }

    // Map<String columnName, Object value>
    public List<Map<String, Object>> queryForList_ListMap() {

        String sql = "Select e.Emp_No, e.Emp_Name from Employee e ";

        // List<Map<String, Object>> queryForList(String sql)
        List<Map<String, Object>> list = this.getJdbcTemplate().queryForList(sql);

        return list;
    }

    // List<Map<String, Object>>
    // queryForList(String sql, Object[] args, int[] argTypes)

    public List<Map<String, Object>> queryForList_ListMap2() {

        String sql = "Select e.Emp_Id,e.Emp_No,e.Emp_Name From Employee e " //
                + " Where e.Hire_Date > ? and e.Salary > ? ";
        //
        Date hireDate = getDateByYear(1981);
        Object[] args = new Object[] { hireDate, 2800 };
        int[] argTypes = new int[] { Types.DATE, Types.DOUBLE };

        // List<Map<String, Object>> queryForList(String sql)
        List<Map<String, Object>> list = this.getJdbcTemplate().queryForList(sql, args, argTypes);

        return list;
    }

    private Date getDateByYear(int year) {
        java.sql.Date date = new java.sql.Date(System.currentTimeMillis());
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        c.set(Calendar.YEAR, year);
        c.set(Calendar.MONTH, Calendar.JANUARY);
        c.set(Calendar.DAY_OF_YEAR, 1);
        return c.getTime();
    }

}

QueryForListReturnListMap_Test.java

package org.o7planning.springjdbc.demo;

import java.sql.SQLException;
import java.util.List;
import java.util.Map;

import org.o7planning.springjdbc.config.AppConfiguration;
import org.o7planning.springjdbc.dao.QueryForListReturnListMapDAO;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class QueryForListReturnListMap_Test {

    public static void main(String[] args) throws SQLException {

        ApplicationContext context = new AnnotationConfigApplicationContext(AppConfiguration.class);

        QueryForListReturnListMapDAO dao = context.getBean(QueryForListReturnListMapDAO.class);

        // Map<String columnName, Object value)
        List<Map<String, Object>> list = dao.queryForList_ListMap2();

        for (Map<String, Object> map : list) {
            System.out.println("-----");
            for (String key : map.keySet()) {
                System.out.println("Key: " + key + " - value: " + map.get(key));
            }
        }
    }

}

Chạy ví dụ:

-----
Key: EMP_ID - value: 7839
Key: EMP_ID - value: E7839
Key: EMP_NAME - value: KING
-----
Key: EMP_ID - value: 7566
Key: EMP_ID - value: E7566
Key: EMP_NAME - value: JONES
...

4. JdbcTemplate.queryForRowSet

// JdbcTemplate.queryForRowSet methods ....

public SqlRowSet queryForRowSet(String sql,
                     Object[] args, int[] argTypes) throws DataAccessException;

public SqlRowSet queryForRowSet(String sql, Object... args)
                                                              throws DataAccessException;

QueryForRowSetReturnSqlRowSetDAO.java

package org.o7planning.springjdbc.dao;

import java.sql.Types;
import java.util.Calendar;
import java.util.Date;

import javax.sql.DataSource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.support.JdbcDaoSupport;
import org.springframework.jdbc.support.rowset.SqlRowSet;
import org.springframework.stereotype.Repository;

@Repository
public class QueryForRowSetReturnSqlRowSetDAO extends JdbcDaoSupport {

    @Autowired
    public QueryForRowSetReturnSqlRowSetDAO(DataSource dataSource) {
        this.setDataSource(dataSource);
    }

    // SqlRowSet queryForRowSet(String sql, Object[] args, int[] argTypes)

    public SqlRowSet queryForRowSet_SqlRowSet() {

        String sql = "Select e.Emp_Id,e.Emp_No,e.Emp_Name From Employee e " //
                + " Where e.Hire_Date > ? and e.Salary > ? ";
        //
        Date hireDate = getDateByYear(1981);
        Object[] args = new Object[] { hireDate, 2800 };
        int[] argTypes = new int[] { Types.DATE, Types.DOUBLE };

        // SqlRowSet queryForRowSet(String sql, Object[] args, int[] argTypes)
        SqlRowSet rowSet = this.getJdbcTemplate().queryForRowSet(sql, args, argTypes);

        return rowSet;
    }

    private Date getDateByYear(int year) {
        java.sql.Date date = new java.sql.Date(System.currentTimeMillis());
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        c.set(Calendar.YEAR, year);
        c.set(Calendar.MONTH, Calendar.JANUARY);
        c.set(Calendar.DAY_OF_YEAR, 1);
        return c.getTime();
    }

}

QueryForRowSetReturnSqlRowSet_Test.java

package org.o7planning.springjdbc.demo;

import java.sql.SQLException;

import org.o7planning.springjdbc.config.AppConfiguration;
import org.o7planning.springjdbc.dao.QueryForRowSetReturnSqlRowSetDAO;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.jdbc.support.rowset.SqlRowSet;

public class QueryForRowSetReturnSqlRowSet_Test {

    public static void main(String[] args) throws SQLException {

        ApplicationContext context = new AnnotationConfigApplicationContext(AppConfiguration.class);

        QueryForRowSetReturnSqlRowSetDAO dao = context.getBean(QueryForRowSetReturnSqlRowSetDAO.class);

        // SqlRowSet
        SqlRowSet rowSet = dao.queryForRowSet_SqlRowSet();

        while (rowSet.next()) {
           
            System.out.println("-----");
            Long empId = rowSet.getLong("Emp_Id"); // Index = 1
            String empNo = rowSet.getString(2); // Index = 2
            String empName = rowSet.getString("Emp_Name"); // Index = 3

            System.out.println("EmpID: " + empId + ", EmpNo: " + empNo + ", EmpName:" + empName);
        }

    }
   
}

Output:

-----
EmpID: 7839, EmpNo: E7839, EmpName:KING
-----
EmpID: 7566, EmpNo: E7566, EmpName:JONES
-----
EmpID: 7902, EmpNo: E7902, EmpName:FORD
-----
EmpID: 7698, EmpNo: E7698, EmpName:BLAKE
...

5. JdbcTemplate.query & RowMapper

// query methods with RowMapper & returns List

public <T> List<T> query(String sql, Object[] args,
            int[] argTypes, RowMapper<T> rowMapper) throws DataAccessException; 


public <T> List<T> query(String sql, Object[] args,
           RowMapper<T> rowMapper) throws DataAccessException;


public <T> List<T> query(String sql, RowMapper<T> rowMapper,
           Object... args) throws DataAccessException;

JdbcTemplate cung cấp một vài phương thức truy vấn, kết quả trả về một danh sách các đối tượng Java. Bạn cần cung cấp một RowMapper định nghĩa các ánh xạ giữa các cột và các trường của class.

QueryWithRowMapperDAO.java

package org.o7planning.springjdbc.dao;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;

import javax.sql.DataSource;

import org.o7planning.springjdbc.model.Department;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.support.JdbcDaoSupport;
import org.springframework.stereotype.Repository;

@Repository
public class QueryWithRowMapperDAO extends JdbcDaoSupport {

    @Autowired
    public QueryWithRowMapperDAO(DataSource dataSource) {
        this.setDataSource(dataSource);
    }

    private static final String BASE_SQL = //
            "Select d.Dept_Id, d.Dept_No, d.Dept_Name from Department d ";

    class DepartmentRowMapper implements RowMapper<Department> {

        @Override
        public Department mapRow(ResultSet rs, int rowNum) throws SQLException {
            Long deptId = rs.getLong("Dept_Id");
            String deptNo = rs.getString("Dept_No");
            String deptName = rs.getString("Dept_Name");
            return new Department(deptId, deptNo, deptName);
        }

    }

    public List<Department> queryDepartment() {
        String sql = BASE_SQL //
                + " Where d.Dept_Id > ? ";

        DepartmentRowMapper rowMapper = new DepartmentRowMapper();
        Object[] args = new Object[] { 20 };

        List<Department> list = this.getJdbcTemplate().query(sql, args, rowMapper);
        return list;
    }

}

Test:

QueryWithRowMapper_Test.java

package org.o7planning.springjdbc.demo;

import java.sql.SQLException;
import java.util.List;

import org.o7planning.springjdbc.config.AppConfiguration;
import org.o7planning.springjdbc.dao.QueryWithRowMapperDAO;
import org.o7planning.springjdbc.model.Department;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class QueryWithRowMapper_Test {

   
    public static void main(String[] args) throws SQLException {

        ApplicationContext context = new AnnotationConfigApplicationContext(AppConfiguration.class);

        QueryWithRowMapperDAO dao = context.getBean(QueryWithRowMapperDAO.class);

        List<Department> list = dao.queryDepartment() ;
       
        for(Department dept: list)  {
            System.out.println("DeptNo: "+ dept.getDeptNo()+" - DeptName: "+ dept.getDeptName());
        }
    }
   
}

Output:

DeptNo: D30 - DeptName: SALES
DeptNo: D40 - DeptName: OPERATIONS
DeptNo: D41 - DeptName: HR
DeptNo: D42 - DeptName: INV

6. JdbcTemplate.query & RowCallbackHandler

JdbcTemplate cung cấp cho bạn một vài phương thức để bạn truy vấn dữ liệu và thao tác với dữ liệu thông qua ResultSet. Dưới đây là các phương thức như vậy:

// JdbcTemplate.query methods & RowCallbackHandler.

public void query(PreparedStatementCreator psc,
           RowCallbackHandler rch) throws DataAccessException;

public void query(String sql, PreparedStatementSetter pss,
           RowCallbackHandler rch) throws DataAccessException;


public void query(String sql, Object[] args, int[] argTypes,
           RowCallbackHandler rch) throws DataAccessException;

public void query(String sql, Object[] args,
           RowCallbackHandler rch) throws DataAccessException;

public void query(String sql, RowCallbackHandler rch,
           Object... args) throws DataAccessException;

RowCallbackHandler interface:

** RowCallbackHandler **

public interface RowCallbackHandler {

   void processRow(ResultSet rs) throws SQLException;

}

Ví dụ:

QueryWithRowCallbackHandlerDAO.java

package org.o7planning.springjdbc.dao;

import java.sql.ResultSet;
import java.sql.SQLException;

import javax.sql.DataSource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.RowCallbackHandler;
import org.springframework.jdbc.core.support.JdbcDaoSupport;
import org.springframework.stereotype.Repository;

@Repository
public class QueryWithRowCallbackHandlerDAO extends JdbcDaoSupport {

    @Autowired
    public QueryWithRowCallbackHandlerDAO(DataSource dataSource) {
        this.setDataSource(dataSource);
    }

    public void queryEmployee() {
        String sql = "Select e.Emp_Id, e.Emp_No, e.Emp_Name,e.Salary from Employee e "//
                + " Where e.Salary > ? ";

        RowCallbackHandler handler = new RowCallbackHandler() {

            @Override
            public void processRow(ResultSet rs) throws SQLException {
                Long empId = rs.getLong("Emp_Id");
                String empNo = rs.getString(2);
                System.out.println(" ---------------- ");
                System.out.println("EmpId:" + empId);
                System.out.println("EmpNo:" + empNo);
            }

        };
        // query(String sql, RowCallbackHandler rch, Object... args)
        this.getJdbcTemplate().query(sql, handler, 2800);
    }

}

QueryWithRowCallbackHandler_Test.java

package org.o7planning.springjdbc.demo;

import java.sql.SQLException;

import org.o7planning.springjdbc.config.AppConfiguration;
import org.o7planning.springjdbc.dao.QueryWithRowCallbackHandlerDAO;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class QueryWithRowCallbackHandler_Test {

   
    public static void main(String[] args) throws SQLException {

        ApplicationContext context = new AnnotationConfigApplicationContext(AppConfiguration.class);

        QueryWithRowCallbackHandlerDAO dao = context.getBean(QueryWithRowCallbackHandlerDAO.class);

        dao.queryEmployee();
    }
   
}

Output:

----------------
EmpId:7839
EmpNo:E7839
----------------
EmpId:7566
EmpNo:E7566
...

7. JdbcTemplate.query & ResultSetExtractor

// JdbcTemplate.query methods with ResultSetExtractor.

public <T> T query(PreparedStatementCreator psc,
                ResultSetExtractor<T> rse) throws DataAccessException;


public <T> T query(String sql, PreparedStatementSetter pss,
                ResultSetExtractor<T> rse) throws DataAccessException;


public <T> T query(String sql, Object[] args, int[] argTypes,
                ResultSetExtractor<T> rse) throws DataAccessException;


public <T> T query(String sql, Object[] args,
                ResultSetExtractor<T> rse) throws DataAccessException;


public <T> T query(String sql, ResultSetExtractor<T> rse,
                Object... args) throws DataAccessException;

Ví dụ:

QueryWithResultSetExtractorDAO.java

package org.o7planning.springjdbc.dao;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import javax.sql.DataSource;

import org.o7planning.springjdbc.model.Department;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.dao.DataAccessException;
import org.springframework.jdbc.core.ResultSetExtractor;
import org.springframework.jdbc.core.support.JdbcDaoSupport;
import org.springframework.stereotype.Repository;

@Repository
public class QueryWithResultSetExtractorDAO extends JdbcDaoSupport {

    @Autowired
    public QueryWithResultSetExtractorDAO(DataSource dataSource) {
        this.setDataSource(dataSource);
    }

    private static final String BASE_SQL = //
            "Select d.Dept_Id, d.Dept_No, d.Dept_Name from Department d ";

    class DepartmentListResultSetExtractor implements ResultSetExtractor<List<Department>> {

        @Override
        public List<Department> extractData(ResultSet rs) throws SQLException, DataAccessException {
            List<Department> list = new ArrayList<Department>();
            while (rs.next()) {
                Long deptId = rs.getLong("Dept_Id");
                String deptNo = rs.getString("Dept_No");
                String deptName = rs.getString("Dept_Name");
                list.add(new Department(deptId, deptNo, deptName));
            }
            return list;
        }

    }

    class DepartmentResultSetExtractor implements ResultSetExtractor<Department> {

        @Override
        public Department extractData(ResultSet rs) throws SQLException, DataAccessException {
            if (rs.next()) {
                Long deptId = rs.getLong("Dept_Id");
                String deptNo = rs.getString("Dept_No");
                String deptName = rs.getString("Dept_Name");
                return new Department(deptId, deptNo, deptName);
            }
            return null;
        }

    }

    public List<Department> queryDepartments() {
        String sql = BASE_SQL //
                + " Where d.Dept_Id > ? ";

        DepartmentListResultSetExtractor rse = new DepartmentListResultSetExtractor();

        // <T> T query(String sql, ResultSetExtractor<T> rse, Object... args)
        List<Department> list = this.getJdbcTemplate().query(sql, rse, 40);
        return list;
    }

    public Department findDepartment(Long deptId) {
        String sql = BASE_SQL //
                + " Where d.Dept_Id = ? ";

        DepartmentResultSetExtractor rse = new DepartmentResultSetExtractor();

        // <T> T query(String sql, ResultSetExtractor<T> rse, Object... args)
        Department dept = this.getJdbcTemplate().query(sql, rse, 40);
        return dept;
    }

}

8. JdbcTemplate.queryForObject

// JdbcTemplate.queryForObject methods:

public <T> T queryForObject(String sql, Object[] args,
                int[] argTypes, RowMapper<T> rowMapper)
        throws DataAccessException; 


public <T> T queryForObject(String sql, Object[] args,
                RowMapper<T> rowMapper) throws DataAccessException;

public <T> T queryForObject(String sql, RowMapper<T> rowMapper,
                Object... args) throws DataAccessException;


public <T> T queryForObject(String sql, Object[] args,
                int[] argTypes, Class<T> requiredType)
        throws DataAccessException;


public <T> T queryForObject(String sql, Object[] args,
                Class<T> requiredType) throws DataAccessException;


public <T> T queryForObject(String sql, Class<T> requiredType,
                Object... args) throws DataAccessException;

Ví dụ:

QueryForObjectDAO.java

package org.o7planning.springjdbc.dao;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Types;
import java.util.Date;

import javax.sql.DataSource;

import org.o7planning.springjdbc.model.Department;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.dao.EmptyResultDataAccessException;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.support.JdbcDaoSupport;
import org.springframework.stereotype.Repository;

@Repository
public class QueryForObjectDAO extends JdbcDaoSupport {

    @Autowired
    public QueryForObjectDAO(DataSource dataSource) {
        this.setDataSource(dataSource);
    }

    private static final String BASE_SQL = //
            "Select d.Dept_Id, d.Dept_No, d.Dept_Name from Department d ";

    class DepartmentRowMapper implements RowMapper<Department> {

        @Override
        public Department mapRow(ResultSet rs, int rowNum) throws SQLException {
            Long deptId = rs.getLong("Dept_Id");
            String deptNo = rs.getString("Dept_No");
            String deptName = rs.getString("Dept_Name");
            return new Department(deptId, deptNo, deptName);
        }

    }

    public Department getDepartment(String deptNo) {
        try {
            String sql = BASE_SQL //
                    + " Where d.Dept_No = ? ";

            DepartmentRowMapper rowMapper = new DepartmentRowMapper();
            Object[] args = new Object[] { deptNo };

            Department dept = this.getJdbcTemplate().queryForObject(sql, args, rowMapper);
            return dept;
        } catch (EmptyResultDataAccessException e) {
            return null;
        }
    }

    public String getDeptNameById(Long deptId) {
        try {
            String sql = "Select d.Dept_Name from Department d "//
                    + " Where d.Dept_Id = ?";
            Object[] args = new Object[] { deptId };

            String deptName = this.getJdbcTemplate().queryForObject(sql, String.class, args);
            return deptName;
        } catch (EmptyResultDataAccessException e) {
            return null;
        }
    }

    public Date getEmpHireDateById(Long empId) {
        try {
            String sql = "Select e.Hire_Date from Employee e "//
                    + " Where e.Emp_Id = ?";
            Object[] args = new Object[] { empId };
            int[] argTypes = new int[] { Types.BIGINT };

            Date hireDate = this.getJdbcTemplate().queryForObject(sql, args, argTypes, Date.class);
            return hireDate;
        } catch (EmptyResultDataAccessException e) {
            return null;
        }
    }

}

Test:

QueryForObject_Test.java

package org.o7planning.springjdbc.demo;

import java.sql.SQLException;
import java.util.Date;

import org.o7planning.springjdbc.config.AppConfiguration;
import org.o7planning.springjdbc.dao.QueryForObjectDAO;
import org.o7planning.springjdbc.model.Department;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class QueryForObject_Test {

    public static void main(String[] args) throws SQLException {

        ApplicationContext context = new AnnotationConfigApplicationContext(AppConfiguration.class);

        QueryForObjectDAO dao = context.getBean(QueryForObjectDAO.class);

        System.out.println(" ------------- ");
        Department dept = dao.getDepartment("D20");

        if (dept != null) {
            System.out.println("DeptNo: " + dept.getDeptNo() + " - DeptName: " + dept.getDeptName());
        } else {
            System.out.println("Department not found!");
        }
        System.out.println(" ------------- ");

        String deptName = dao.getDeptNameById(30L);
        System.out.println("Dept Name by Id 30: " + deptName);

        System.out.println(" ------------- ");

        Date hireDate = dao.getEmpHireDateById(7839L);
        System.out.println("HireDate by EmpId 7839: " + hireDate);

    }

}

Output:

-------------
DeptNo: D20 - DeptName: RESEARCH
 -------------
Dept Name by Id 30: SALES
 -------------
 HireDate by EmpId 7839: 1981-11-17 00:00:00.0

Hướng dẫn và ví dụ Spring JDBC

1. Modal Classes

2. JdbcTemplate.queryForList -> List

3. JdbcTemplate.queryForList -> List<Map>

4. JdbcTemplate.queryForRowSet

5. JdbcTemplate.query & RowMapper

6. JdbcTemplate.query & RowCallbackHandler

7. JdbcTemplate.query & ResultSetExtractor

8. JdbcTemplate.queryForObject

9. TODO ..

Các hướng dẫn Spring Boot

Các hướng dẫn Spring Boot

Các bài viết mới nhất

Hướng dẫn và ví dụ Spring JDBC

1. Modal Classes

2. JdbcTemplate.queryForList -> List

3. JdbcTemplate.queryForList -> List&lt;Map>

4. JdbcTemplate.queryForRowSet

5. JdbcTemplate.query & RowMapper

6. JdbcTemplate.query & RowCallbackHandler

7. JdbcTemplate.query & ResultSetExtractor

8. JdbcTemplate.queryForObject

9. TODO ..

Các hướng dẫn Spring Boot

Các hướng dẫn Spring Boot

Các bài viết mới nhất

3. JdbcTemplate.queryForList -> List<Map>