java ibatis 读取mysql blob类型乱码 spring mvc文件下载csv文件乱码

java 中实体类类型 string mysql 中blob 读取后乱码

一、

将实体类中类型修改为

byte[] contentDesc;

sql-map中修改

<result column="ContentDesc" jdbcType="BLOB" property="contentDesc" javaType="byte" />

输出时

System.out.println(new String(wxcircleDTO.getContentDesc(),"UTF-8"));

输出中文了

spring mvc 下载文件

读取数据库数据，保存为文件后下载。csv文件中文乱码

outwriter = new OutputStreamWriter(fileout,"GBK");

一定要是GBK，UTF-8会乱码掉

生成文件以及下载action方法

@RequestMapping(value="/downloadCSV.do")
public ResponseEntity<byte[]> downloadCSV(HttpServletResponse res){

List<WxDataDto> list = wxcircleDao.getDatas();

System.out.println("数据大小：  " + list.size());
FileOutputStream fileout = null;
OutputStreamWriter outwriter = null;
BufferedWriter bufferwri = null;
CSVWriter csvwr = null;
String save = "C:\\Users\\data.csv";
try {
fileout = new FileOutputStream(save);
outwriter = new OutputStreamWriter(fileout,"GBK");
bufferwri = new BufferedWriter(outwriter);
csvwr = new CSVWriter(bufferwri,',');

if(list != null && list.size() != 0){

//写入头
String[] record = {"t_id(表id)","id","username","createTime","private1",
"contentDesc","city","longitude","latitude","poiAddr",
"contentUrl","poiName", "sourceNickName","sourceUserName",
"publicUserName","statictData","title","description","contentStyle",
"mediaid","mediaurl","mediathumb","mediaDescription"};

csvwr.writeNext(record);//写入新行数据

for (WxDataDto wxcircleDTO : list) {
//					if(wxcircleDTO.getT_id() != 155)
//						continue;
//					bufferwri.append(wxcircleDTO.getId() + ",");

record[0] = wxcircleDTO.getT_id() + "";
record[1] = wxcircleDTO.getId() + "";
record[2] = wxcircleDTO.getUsername();
SimpleDateFormat format = new SimpleDateFormat( "yyyy-MM-dd HH:mm:ss" );
record[3] = format.format(Long.parseLong(wxcircleDTO.getCreateTime()) * 1000);
record[4] = wxcircleDTO.getPrivate1() + "";
record[5] = new String(wxcircleDTO.getContentDesc(),"UTF-8");
record[6] = wxcircleDTO.getCity();
record[7] = wxcircleDTO.getLongitude();
record[8] = wxcircleDTO.getLatitude();
record[9] = wxcircleDTO.getPoiAddr();
record[10] = wxcircleDTO.getContentUrl();
record[11] = wxcircleDTO.getPoiName();
record[12] = wxcircleDTO.getSourceNickName();
record[13] = wxcircleDTO.getSourceUserName();
record[14] = wxcircleDTO.getPublicUserName();
record[15] = wxcircleDTO.getStatictData();
record[16] = wxcircleDTO.getTitle();
record[17] = wxcircleDTO.getDescription();
record[18] = wxcircleDTO.getContentStyle();
record[19] = wxcircleDTO.getMediaid() + "";
record[20] = wxcircleDTO.getMediaurl();
record[21] = wxcircleDTO.getMediathumb();
record[22] = wxcircleDTO.getMediaDescription();

csvwr.writeNext(record);//写入新行数据
csvwr.flush();
//					String DEFAULT_CHARSET = "UTF-8";
//					ByteArrayInputStream bis = new ByteArrayInputStream(wxcircleDTO.getContentDesc().getBytes(DEFAULT_CHARSET));
//					StringBuffer sb = new StringBuffer(1024);
//					int value = 0;
//					while((value = bis.read()) != -1){
//						sb.append((char)value);
//					}
//			        byte[] returnValue = null;
//			        if (null != blob) {
//			            returnValue = blob.getBytes(1, (int) blob.length());
//			        }
//					String desc = new String(.getBytes(),);
//					System.out.println(sb.toString());
//					System.out.println(new String(wxcircleDTO.getContentDesc().getBytes(),"UTF-8"));

//					bufferwri.append(wxcircleDTO.getT_id() + "");
//					System.out.println(wxcircleDTO.getContentDesc().toString());
//					bufferwri.append(wxcircleDTO.getContentDesc() + ",");
//					bufferwri.append(wxcircleDTO.getContentStyle() + ",");
//					bufferwri.append(wxcircleDTO.getContentUrl() + ",");
//					SimpleDateFormat format = new SimpleDateFormat( "yyyy-MM-dd HH:mm:ss" );
//					String time = format.format(Long.parseLong(wxcircleDTO.getCreateTime()) * 1000);
//					bufferwri.append(time + ",");
//					bufferwri.append(wxcircleDTO.getDescription() + ",");
//					bufferwri.append(wxcircleDTO.getLatitude());

//					bufferwri.append("\r\n");
csvwr.flush();
}

}
bufferwri.flush();

/**
* 不可以打印否则无法下载
*/
//			FileInputStream fi = new FileInputStream(save);
//			OutputStream out = res.getOutputStream();
//			int dex;
//			while((dex = fi.read()) != -1){
//				out.write(dex);
//			}
//			out.flush();
//
//			if(out != null){
//				out.close();
//			}
//			if(fi != null){
//				fi.close();
//			}

//			File fi = new File(save);
//			InputStream is = new FileInputStream(fi);
//			int dex;
//			while((dex = is.read()) != -1){
//				res.getOutputStream().write(dex);
//			}
} catch (Exception e) {
e.printStackTrace();
}finally{
if(csvwr != null){
try {
csvwr.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if(bufferwri != null){
try {
bufferwri.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if(outwriter != null){
try {
outwriter.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if(fileout != null){
try {
fileout.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

/**
* 返回页面下载
*/
try {
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
headers.setContentDispositionFormData("attachment", "data_.csv");
return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(new File(save)),
headers, HttpStatus.CREATED);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}

spring-servlet。xml配置

<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
<property name="messageConverters">
<list >
<!-- //把ByteArray加在Json前面 必须加入，否则无法下载   文件下载byte方式   -->
<bean class="org.springframework.http.converter.ByteArrayHttpMessageConverter"/>
<ref bean="mappingJacksonHttpMessageConverter" />
</list>
</property>
</bean>

mysql blob 对应java

byte[] contentDesc;//

sql -map
<pre name="code" class="html"><result column="ContentDesc" jdbcType="BLOB" property="contentDesc" javaType="byte" />