Struts2存取Oracle Blob字段实现上传下载
1.文件上传的实现（多个附件）
本例以上传多个附件为例，实现Struts2保存Oracle Blob字段的上传功能
需要前台传到后台的参数如下：
(1).用户上传的所有附件列表：private List<File> attachments;
(2).用户上传的所有附件名，用逗号分隔，例如:附件1,附件2,附件3
private String attachmentFileName;
(3).getter/setter方法省略
(4).上传附件的具体实现
Action代码：
if(attachmentFileName!=null){
//分割附件名
String name[] = attachmentFileName.split(", ");
int i = 0;
for(File f : attachment){
//循环获得输入流
InputStream in = new FileInputStream(f);
//调用Service上传的方法
this.checkWorkService.uploadAttach(in, name[i++].trim());
in.close();
}
}
Service代码：
public CheckWorkRecordAttach uploadAttach(InputStream inputStream,
String attachmentName) throws Exception {
//输出流
ByteArrayOutputStream bytestream = new ByteArrayOutputStream();
int ch;
byte[] buffer = new byte[1024];
//编码转换，后经测试发现无用
// String str = new String(buffer,"utf-8");
// String str2 = new String(str.getBytes("iso-8859-1"),"utf-8");
// byte buffers[] = str2.getBytes();
while ((ch = inputStream.read(buffer)) > 0) {
bytestream.write(buffer, 0, ch);
}
// 将输入流写成BYTE数组
byte[] data = bytestream.toByteArray();
bytestream.close();
// 将BYTE数组变成BLOB对象
Blob attachmentCont = Hibernate.createBlob(data);
//保存到数据库
CheckWorkRecordAttach attach = new CheckWorkRecordAttach();
attach.setAttachmentName(attachmentName);
attach.setAttachmentUuid(uuid);
attach.setUploadTime(new Date());
attach.setState(0);
attach.setAttachmentCont(attachmentCont);
attach = this.getCheckWorkRecordAttachDao().save(attach);
return attach;
}
文件上传完成！！
2.文件下载的实现（修复附件中文名乱码）
需要前台传到后台的参数如下：
(1).附件名：private String attachmentFileName;
(2).附件ID：private String attachId;
(3).getter/setter方法省略
/*附件下载*/
/*前台代码*/
function download(id,fileName){
window.location.href = "../downloadAttach/assignWork_downLoad?attachmentFileName="+fileName+"&&attachId="+id;
}
(4).下载附件的后台代码实现
//附件名的getter，setter方法，防止中文名乱码
public String getAttachmentFileName() {
return this.attachmentFileName;
}
public void setAttachmentFileName(String attachmentFileName) {
try {
this.attachmentFileName = new String(attachmentFileName.getBytes("ISO-8859-1"), "utf-8");
} catch (UnsupportedEncodingException e) {
logger.error("附件名转换失败", e);
this.attachmentFileName = "未知";
};
}
Action代码（需要返回InputStream）：
/**
* 附件下载
* @return
*/
public String downLoad(){
try {
//防止中文附件名乱码
ServletActionContext.getResponse().setHeader("Content-Disposition", "attachment;fileName="
+ java.net.URLEncoder.encode(this.attachmentFileName,"UTF-8"));
inputStream = this.assignWorkService.downLoad(Integer.parseInt(attachId));
return SUCCESS;
} catch (Exception e) {
e.printStackTrace();
return ERROR;
}
}
Service代码（返回InputStream）：
/**
* 附件下载
*/
@Transactional
public InputStream downLoad(int attachId) throws Exception {
//根据ID获取附件
PersonalWorkReportAttach personalWorkReportAttach = this.personalWorkReportAttachDao.get(attachId);
//附件内容
Blob blob = personalWorkReportAttach.getAttachmentCont();
//获得InputStream
InputStream inputStream = blob.getBinaryStream();
byte[] buffer = new byte[1024];
int ch;
//OutPotStream
ByteArrayOutputStream out= new ByteArrayOutputStream();
//下面将BLOB数据写入文件
String str = new String(buffer,"iso-8859-1");
String str2 = new String(str.getBytes("utf-8"),"iso-8859-1");
byte buffers[] = str2.getBytes();
while((ch = inputStream.read(buffer))>0){
out.write(buffers,0,ch);
}
//依次关闭
out.close();
inputStream.close();
return new ByteArrayInputStream(out.toByteArray());
}
Struts.xml的配置
<!-- 附件下载 -->
<package name="downloadAttach" namespace="/downloadAttach" extends="struts-default">
<action name="assignWork_*" class="AssignWorkAction" method="{1}">
<result name="success" type="stream">
<param name="inputName">inputStream</param>
<param name="contentDisposition">attachment;filename="${attachmentFileName}"</param>
<param name="bufferSize">4096</param>
</result>
</action>
</package>
下载附件功能完成！！