mybatis之XMLLanguageDriver使用方式例子

mybatis中的XMLLanguageDriver类出现的一大原因在于:使用注解配置sql语句没有使用xml的方式灵活和强大，为了弥补这种缺陷，XMLLanguageDriver出现了。下面只是简单的举个例子，贴点代码，不多做解释。因为对于使用过mybatis的人，一看就明白。

SimpleSelectInLangDriver

package com.core.mybatis.languageDriver;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.ibatis.mapping.SqlSource;
import org.apache.ibatis.scripting.LanguageDriver;
import org.apache.ibatis.scripting.xmltags.XMLLanguageDriver;
import org.apache.ibatis.session.Configuration;

//一次编写即可
public class SimpleSelectInLangDriver extends XMLLanguageDriver implements LanguageDriver {

    private static final Pattern inPattern = Pattern.compile("\\(#\\{(\\w+)\\}\\)");

    @Override
    public SqlSource createSqlSource(Configuration configuration, String script, Class<?> parameterType) {

        Matcher matcher = inPattern.matcher(script);
        if (matcher.find()) {
            script = matcher.replaceAll("<foreach collection=\"$1\" item=\"_item\" open=\"(\" "
                    + "separator=\",\" close=\")\" >#{_item}</foreach>");
        }

        script = "<script>" + script + "</script>";
        return super.createSqlSource(configuration, script, parameterType);
    }
}

SimpleUpdateLangDriver

package com.core.mybatis.languageDriver;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.ibatis.mapping.SqlSource;
import org.apache.ibatis.scripting.LanguageDriver;
import org.apache.ibatis.scripting.xmltags.XMLLanguageDriver;
import org.apache.ibatis.session.Configuration;

public class SimpleUpdateLangDriver extends XMLLanguageDriver implements LanguageDriver{

    private final Pattern inPattern = Pattern.compile("\\(#\\{(\\w+)\\}\\)");

    @Override
    public SqlSource createSqlSource(Configuration configuration, String script, Class<?> parameterType) {
        Matcher matcher = inPattern.matcher(script);
        if (matcher.find()) {
            StringBuilder sb = new StringBuilder();
            sb.append("<set>");

            sb.append("<if test=\"name != null \">   name = #{name},</if>");
            sb.append("<if test=\"price != null \"> price = #{price},</if>");


         /*   for (Field field : parameterType.getDeclaredFields()) {
                String tmp = "<if test=\"_field != null\">_column=#{_field},</if>";
                sb.append(tmp.replaceAll("_field", field.getName()).replaceAll("_column",
                        CaseFormat.LOWER_CAMEL.to(CaseFormat.LOWER_UNDERSCORE, field.getName())));
            }*/

            sb.deleteCharAt(sb.lastIndexOf(","));
            sb.append("</set>");

            script = matcher.replaceAll(sb.toString());
            script = "<script>" + script + "</script>";
        }

        return super.createSqlSource(configuration, script, parameterType);
    }
}

BookDao是dao层

package com.springmvc.family.dao;

import java.util.List;

import org.apache.ibatis.annotations.Lang;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;

import com.core.mybatis.languageDriver.SimpleSelectInLangDriver;
import com.core.mybatis.languageDriver.SimpleUpdateLangDriver;
import com.springmvc.family.model.Book;

/**
 * @author lihong 2016年6月24日 下午2:12:19
 * @version v1.0
 */
@Mapper
public interface BookDao
{
    /**
     * @param book 
     * @author lihong 2016年6月24日 下午2:12:39
     * @since v1.0
     */
    public void addBook(Book book);

    /**
     * 与addBook功能相同，此处是为了测试两种插入数据并获取主键的方法
     * @param book void
     * @author lihong 2016年6月24日 下午2:58:33
     * @since v1.0
     */
    public void insert(Book book);

    /**
     * @return List<Book>
     * @author lihong 2016年6月24日 下午2:12:59
     * @since v1.0
     */
    public List<Book> getAll(Book book);


    @Select("SELECT * FROM book WHERE id IN (#{idList})")
    @Lang(SimpleSelectInLangDriver.class)
    List<Book> getBookByIdInBatch(@Param("idList") List<Integer> idList);


    @Update("UPDATE book (#{book}) WHERE id = #{id}")
    @Lang(SimpleUpdateLangDriver.class)
    void updateUsersById(Book book);

}

Book 类是实体类

@Alias("Book")
public class Book implements java.io.Serializable
{
    /**
     * @Fields serialVersionUID :
     */
    private static final long serialVersionUID = -8019185784560242092L;
    private int id;
    private String name;
    private float price;

    /**
     * @author lihong 2016年6月24日 下午2:11:59
     * @since v1.0
     */
    public Book()
    {

    }

    /**
     * @return the id
     */
    public int getId()
    {
        return id;
    }
    /**
     * @param id the id to set
     */
    public void setId(int id)
    {
        this.id = id;
    }
    /**
     * @return the name
     */
    public String getName()
    {
        return name;
    }
    /**
     * @param name the name to set
     */
    public void setName(String name)
    {
        this.name = name;
    }
    /**
     * @return the price
     */
    public float getPrice()
    {
        return price;
    }
    /**
     * @param price the price to set
     */
    public void setPrice(float price)
    {
        this.price = price;
    }





}

BookDaoTest 类是使用测试用例

import java.util.ArrayList;
import java.util.List;

import org.junit.Test;
import org.springframework.beans.factory.annotation.Autowired;

import com.springmvc.AnnotationServiceTest;
import com.springmvc.family.dao.BookDao;
import com.springmvc.family.model.Book;

/**
 * @author lihong 2016年6月24日 下午2:37:49
 * @version v1.0
 */
public class BookDaoTest extends AnnotationServiceTest
{

    @Autowired
    private BookDao bookDao;

    private Book getBook()
    {
        Book book = new Book();
        book.setName("测试生成的书名");
        book.setPrice(2.32f);
        return book;
    }

    /**
     * 测试插入数据后返回自增的主键id值
     * @author lihong 2016年6月24日 下午2:45:56
     * @since v1.0
     */
    @Test
    public void testAdd()
    {
        for(int i = 0; i < 10; i++)
        {
            Book book = getBook();
            bookDao.addBook(book);
            System.out.println("数据库自增主键策略返回的id是:  " + book.getId() + "         ");
        }

    }

    /**
     *  采用另外一种配置方式测试插入数据后返回自增的主键id值
     * @author lihong 2016年6月24日 下午3:02:09
     * @since v1.0
     */
    @Test
    public void testInsert()
    {
        for(int i = 0; i < 10; i++)
        {
            Book book = getBook();
            bookDao.insert(book);
            System.out.println("数据库自增主键策略返回的id是:  " + book.getId() + "         ");
        }

    }

    /**
     * @author lihong 2016年6月24日 下午2:49:51
     * @since v1.0
     */
    @Test
    public void testGetAll()
    {
        for(int i = 0; i < 4; i++) { //循环是为了验证是否有缓存，是否只是到数据库查询一次
            Book book = new Book();
            book.setName("测试生成的书名");
            book.setPrice(2.32f);

            List<Book> all = bookDao.getAll(book);
            for(Book bk : all)
            {
                System.out.print("id: " + bk.getId() + "  ");
                System.out.print("name: " + bk.getName() + "  ");
                System.out.print("price: " + bk.getPrice() + "  ");
                System.out.println("-----------------------------------------------------");
            }
        }
    }


    @Test
    public void testGetInBatchById() {

        List<Integer> idList = new ArrayList<Integer>();
        idList.add(24);
        idList.add(25);
        List<Book> books = bookDao.getBookByIdInBatch(idList);
        for(Book book : books)
        {
            System.out.print("id: " + book.getId() + "  ");
            System.out.print("name: " + book.getName() + "  ");
            System.out.print("price: " + book.getPrice() + "  ");
            System.out.println("-----------------------------------------------------");
        }

    }

    @Test
    public void testUpdateBookById() {
        Book book = new Book();
        book.setId(23);
        book.setName("***************");
        book.setPrice(2.32f);
        bookDao.updateUsersById(book);
    }


}