Mybatis读取Oracle数据库Blob字段，输出原文件

package com.cntaiping.tpa.bean;

import java.sql.Blob;

public class AttachmentBean {
    private Integer id;
    private String finename;
    private Long contentSize;
    private String fileType;
    //Java的Object类型来对应数据库的BLOB类型，后边将Object转化成Blob类型
    private Object content;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getFilename() {
        return finename;
    }

    public void setFileName(String finename) {
        this.finename= finename;
    }

    public Long getContentSize() {
        return contentSize;
    }

    public void setContentSize(Long contentSize) {
        this.contentSize = contentSize;
    }

    public String getFileType() {
        return fileType;
    }

    public void setFileType(String fileType) {
        this.fileType = fileType;
    }

    public Object getContent() {
        return content;
    }

    public void setContent(Object content) {
        this.content = content;
    }


}

package com.cntaiping.tpa.dao;

import com.cntaiping.tpa.bean.AttachmentBean;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Result;
import org.apache.ibatis.annotations.Results;
import org.apache.ibatis.annotations.Select;

import java.util.List;

public interface AttachmentDao {

    @Select("select ID,FILENAME,CONTENTSIZE,FILETYPE,CONTENT from attachment")
    @Results({
            @Result(column="ID",property="id"),
            @Result(column="FILENAME",property="filename"),
            @Result(column="CONTENTSIZE",property="contentSize"),
            @Result(column="FILETYPE",property="fileType"),
            @Result(column="CONTENT",property="content"),
    })
    List<AttachmentBean> getAttachmentList();
}

package com.cntaiping.tpa.service.impl;

import com.cntaiping.tpa.bean.AttachmentBean;
import com.cntaiping.tpa.dao.AttachmentDao;
import com.cntaiping.tpa.dao.datasource.DataSource;
import com.cntaiping.tpa.service.AttachmentService;
import oracle.sql.BLOB;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Isolation;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;
import java.io.*;
import java.sql.SQLException;
import java.util.List;

@Transactional(propagation=Propagation.REQUIRED,isolation=Isolation.DEFAULT)
@Service("attachmentService")
@DataSource("ORACLE")
public class AttachmentServiceImpl implements AttachmentService {
    @Autowired
    private AttachmentDao attachmentDao;

    @Override
    public List<AttachmentBean> getAttachmentList() {
        return attachmentDao.getAttachmentList();
    }


    @Override
    public int parseAttachmentList() throws SQLException {
        int i=0;
        BLOB blob=null;
        List<AttachmentBean> list=attachmentDao.getAttachmentList();
        for(AttachmentBean a:list){
            blob=(BLOB)a.getContent();
            if(blob!=null) {
                i++;
                writeNewFile(blob.getBinaryStream(), "D:\\a\\" + a.getObjId() + a.getName() + "." + a.getFileType());
            }else{
                System.out.println("空附件："+a.getName());
            }
        }
        return 0;
    }



    private  boolean writeNewFile(InputStream in,String savePath){
        File file=new File(savePath);
        OutputStream os=null;
        try {
            os= new BufferedOutputStream(new FileOutputStream(savePath));
            int len = 0;
            byte[] buffer = new byte[1024];
            while ((len = in.read(buffer)) > 0) {
                os.write(buffer, 0, len);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        try {
            os.close();
            in.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return true;
    }
    private boolean writeNewFile(byte[] data,String savePath){
        File file=new File(savePath);
        OutputStream os = null;
        try {
            os = new FileOutputStream(file);
            os.write(data, 0, data.length);
        } catch (Exception e) {
            e.printStackTrace();
        }
        try {
            os.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return true;
    }
}