java 从实体，mapper,xml,service,iml,controller怎么批量插入[{ "id": 1,"bill_list": [ {"name": "附件1"}]}]该数据

要在Java中实现批量插入数据，你需要按照以下步骤进行操作：实体类、Mapper接口、XML映射文件、Service层和Controller层。以下是一个完整的示例：

### 1. 实体类

// MainEntity.java
public class MainEntity {
    private Integer id;
    private List<Bill> billList;

    // Getters and Setters
}

// Bill.java
public class Bill {
    private String name;

    // Getters and Setters
}

### 2. Mapper接口

// MainMapper.java
import org.apache.ibatis.annotations.Param;
import java.util.List;

public interface MainMapper {
    void batchInsert(@Param("entities") List<MainEntity> entities);
}

### 3. XML映射文件

<!-- MainMapper.xml -->
<mapper namespace="com.example.mapper.MainMapper">
    <insert id="batchInsert" parameterType="java.util.List">
        INSERT INTO main_table (id) VALUES
        <foreach collection="entities" item="entity" separator=",">
            (#{entity.id})
        </foreach>
    </insert>
    <insert id="batchInsertBill" parameterType="java.util.List">
        INSERT INTO bill_table (main_id, name) VALUES
        <foreach collection="entities" item="entity" index="index" separator=",">
            <foreach collection="entity.billList" item="bill" separator=",">
                (#{entity.id}, #{bill.name})
            </foreach>
        </foreach>
    </insert>
</mapper>

### 4. Service层

// MainService.java
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;

@Service
public class MainService {
    @Autowired
    private MainMapper mainMapper;

    public void batchInsert(List<MainEntity> entities) {
        mainMapper.batchInsert(entities);
        mainMapper.batchInsertBill(entities);
    }
}

### 5. Controller层

// MainController.java
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.util.List;

@RestController
@RequestMapping("/main")
public class MainController {
    @Autowired
    private MainService mainService;

    @PostMapping("/batchInsert")
    public String batchInsert(@RequestBody List<MainEntity> entities) {
        mainService.batchInsert(entities);
        return "Success";
    }
}

### 6. 数据库表

假设你有两张表：`main_table` 和 `bill_table`。

CREATE TABLE main_table (
    id INT PRIMARY KEY
);

CREATE TABLE bill_table (
    id INT AUTO_INCREMENT PRIMARY KEY,
    main_id INT,
    name VARCHAR(255),
    FOREIGN KEY (main_id) REFERENCES main_table(id)
);

### 7. 数据示例

[
    {
        "id": 1,
        "bill_list": [
            {"name": "附件1"}
        ]
    }
]

通过以上步骤，你可以在Java中实现批量插入数据的功能。