Hibernate的Annotation中实体BLOB、CLOB类型的注解

在Hibernate Annotation中，实体BLOB、CLOB类型的注解与普通的实体属性有些不同，具体操作如下： 

 

BLOB类型的属性声明为byte[]或者java.sql.Blob： 

 

@Lob 

@Basic(fetch=FetchType.LAZY) 

@Column(name="IMGS", columnDefinition="BLOB", nullable=true)

private byte[] imgs; 

 

public byte[] getImgs() { 

   return this.imgs; 

} 

 

public void setImgs(byte[] imgs) { 

   this.imgs= imgs; 

} 

 

//下面的例子就是用的java.sql.Blob

@Lob 

@Basic(fetch=FetchType.LAZY) 

@Column(name="IMGS", columnDefinition="BLOB", nullable=true)

private Blob imgs; 

 

public Blob getImgs() { 

   return this.imgs; 

} 

 

public void setImgs(Blob imgs) { 

   this.imgs= imgs; 

}

 

 

 

CLOB类型的属性声明为String或java.sql.Clob即可： 

 

@Lob 

@Basic(fetch = FetchType.EAGER) 

@Column(name="REMARK", columnDefinition="CLOB", nullable=true)

private String remark; 

 

public String getRemark() { 

   return this.remark; 

} 

 

public void setRemark(String remark) { 

   this.remark = remark; 

}

 

@Lob 

@Basic(fetch = FetchType.EAGER) 

@Column(name="REMARK", columnDefinition="CLOB", nullable=true)

private Clob remark; 

 

public Clob getRemark() { 

   return this.remark; 

} 

 

public void setRemark(Clob remark) { 

   this.remark = remark; 

}

 

【注】：在Oracle数据库中byte[]和String存储的是二进制流文件，而Blob和Clob存储的是原文件，如果Clob字

        符串中出现中文乱码情况，请检查数据库的编码是否支持中文。

 

上面是Oracle和DB2数据库的写法，如果是MySQL数据库写法如下：

@Lob 

@Basic(fetch = FetchType.EAGER) 

@Column(name="REMARK", columnDefinition="TEXT", nullable=true)

private String remark; 

 

public String getRemark() { 

   return this.remark; 

} 

 

public void setRemark(String remark) { 

   this.remark = remark; 

}

--------------------------------------------------------------------------------------------------

也可直接把字段属性直接定义成Blob类型。

例如插入操作：

receiptSample_edit.jsp文件的部分代码片段：

<form method="post" name="theForm" id="theForm" action="" enctype="multipart/form-data">

    <td height="20" align="right">请选择图片：</td>

    <td align="left">

<input type="file" name="filename" id="filename" class="content"/>

    </td>

</form>

 

receiptSample_edit.js文件的保存方法部分代码片段：

var imageName = $("#filename").val();

var img = imageName.lastIndexOf(".");

var imgNa = imageName.substring(img);

var imgfrom = imgNa.toLowerCase();

if (imageName != "") {

    if (imgfrom != ".gif" && imgfrom != ".jpg" && imgfrom != ".bmp") {

        alert("不支持的图片类型" + imgNa);

        return;

     }

}

$("#theForm").attr("action", "editReceiptSample.do");

$("#theForm").submit();    //注意是submit提交，不是ajax提交的

 

ReceiptSampleCtrl.java文件中的方法：

import org.springframework.web.multipart.MultipartFile;

import org.springframework.web.multipart.MultipartHttpServletRequest;

 

@RequestMapping(value = "editReceiptSample.do")

private String editReceiptSample(HttpServletRequest request, ReceiptSampleVO rsVo) throws Exception {

   Map parmMap = getParmMap(request);

   MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request;

   MultipartFile file = multipartRequest.getFile("filename");

 

   receiptSampleService.saveEditReceipt(rsVo, getGfmisAllUserId(request), parmMap, file);

   return "receiptsystem/receipttypemanage/receiptSample_list";

}

 

ReceiptSampleServiceImpl.java文件中的方法：

public void saveEditReceipt(ReceiptSampleVO rsVO, String userId, Map map, MultipartFile file) throws IOException{

   ReceiptSample rs = receiptSampleDao.findUnique("select rs from ReceiptSample rs where rs.receiptSampleId = ?", new Object[]{Long.parseLong(receiptSampleId)});

   if (file.getSize() != 0) {

       rs.setImgContent(Hibernate.createBlob(file.getInputStream()));

       rs.setImgUploadTime(new Date());

       rs.setImgUploadUserId(Long.parseLong(userId));

   }

   receiptSampleDao.save(rs);

}

 

例如读取操作：

@Entity

@Table(name = "R_RECEIPT_SAMPLE", schema = "GFMIS_ALL")

public class ReceiptSample implements Serializable{

   @Id

    @Column(name = "RECEIPT_SAMPLE_ID")

    @SequenceGenerator(name = "RECEIPT_SAMPLE_ID_GENERATOR", sequenceName = "GFMIS_ALL.SEQ_RECEIPT_SAMPLE_ID", allocationSize = 1)

    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "RECEIPT_SAMPLE_ID_GENERATOR")

    private Long receiptSampleId;

 

    @Column(name = "IMG_CONTENT")

    private Blob imgContent;

 

    public Blob getImgContent() {

        return imgContent;

    }

 

    public void setImgContent(Blob imgContent) {

        this.imgContent = imgContent;

    }

}

 

ReceiptSampleServiceImpl.java文件中的方法：

@Override

public Blob showImg(Long imageId, HttpServletResponse rep) throws Exception{

   Blob imgCount;

   imgCount = receiptSampleDao.get(imageId).getImgContent();

   OutputStream output = null;

   InputStream input = null;

   try {

       final String CONTENT_TYPE = "plain-text/txt;charset=" + "GB2312";

       rep.reset();

       rep.setContentType(CONTENT_TYPE);

       BusinessException.throwWhenNull(imgCount,"该票据类型默认版本没有票样图片信息");

       input = imgCount.getBinaryStream();

//     rep.setHeader("Content-Disposition", "attachment;filename=" + filename + "");

//     bos1.close();

       output = rep.getOutputStream();

       byte data[] = new byte[4096];

       int size = input.read(data);

       while (size != -1) {

            output.write(data, 0, size);

            size = input.read(data);

       }

       output.flush();

    }finally {

        try {

             if (input != null)

                  input.close();

             if (output != null)

                  output.close();

        } catch (IOException e) {

             e.printStackTrace();

        }

    }

    return imgCount;

}

 

ReceiptSampleCtrl.java文件中的方法：

@RequestMapping(value = "viewImg.do")

public String viewImg(HttpServletRequest request, HttpServletResponse rep) throws Exception {

   Map parmMap = getParmMap(request);

   String imgName = (String) parmMap.get("imageId");

   Blob img = receiptSampleService.showImg(Long.parseLong(imgName), rep);

   request.setAttribute("img", img);

   return "receiptsystem/receipttypemanage/ReceiptSampleImg_show";

}

 

ReceiptSampleImg_show.jsp文件中的内容：

<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<%@ page isELIgnored="false" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">

<head>

    <title></title>

    <%@include file="/receiptcommon/commonHead.jsp" %>

    <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>

    <meta http-equiv="Expires" CONTENT="0"/>

    <meta http-equiv="Pragma" CONTENT="no-cache"/>

</head>

<body>

<table>

    <tr>

        <td>

            <c:choose>

                <c:when test="${img != null}">

                    ${img}

                </c:when>

                <c:otherwise>

                    没有图片

                </c:otherwise>

            </c:choose>

        </td>

    </tr>

</table>

</body>

</html>