如何使用java将doc,pdf和图像文件保存到mysql数据库?
我试图使用hibernate,jsf和mysql将.doc
,.pdf
,.txt
和图像文件保存到我的数据库中。如何使用java将doc,pdf和图像文件保存到mysql数据库?
我已经创建了一个列来保存BLOB类型的文件。如果我正在保存.txt
类型,则会正确保存文件。
如果我想保存任何其他格式的文件,那么我得到一个异常。 在我的豆中,我创建了一个字段名称:byte[] file;
我如何正确保存而没有任何异常?我是否需要为mysql列更改数据类型或为java类使用不同的字段?
(响应BalusC)
这是我使用的文件写入的代码。我正在使用fileInputStream
,然后使用hibernate框架保存文件。
Iterator iter = items.iterator();
while (iter.hasNext()) {
FileItem item = (FileItem) iter.next();
if (item.isFormField()) {
String name = item.getFieldName();
String value = item.getString();
} else {
String fieldName = item.getFieldName();
String fileName = item.getName();
String contentType = item.getContentType();
boolean isInMemory = item.isInMemory();
long sizeInBytes = item.getSize();
byte[] fileInBytes=item.get();
try {
File uploadedFile = new File("/home/db/webApp", fileName);
uploadedFile.createNewFile();
FileInputStream fileInputStream = new FileInputStream(uploadedFile);
//convert file into array of bytes
fileInputStream.read(fileInBytes);
fileInputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
UploadedFile object= new UploadedFile();
object.setFile(fileInBytes);
uploadedObject.setFileName(fileName);
session.save(object);
UploadedFile
是JSF管理的bean:
public class UploadedFile{
private String fileName;
private byte[] file;
/**
* @return the fileName
*/
public String getFileName() {
return fileName;
}
/**
* @param fileName the fileName to set
*/
public void setFileName(String fileName) {
this.fileName = fileName;
}
/**
* @return the file
*/
public byte[] getFile() {
return file;
}
/**
* @param file the file to set
*/
public void setFile(byte[] file) {
this.file = file;
}
}
和我的数据库表有以下结构:
Create UploadFile(FILE_NAME` VARCHAR(1000) NOT NULL,
`FILE` BLOB NOT NULL);
其更好地将文件保存在一个位置 和保存位置数据库
也许在一些非常微不足道的情况下,但通常建议将二进制数据存储在文件系统而不是数据库中并不是一个好主意。 – jarnbjo 2011-01-10 12:58:24
@jarnbjo这取决于。想象一下你有一个社交网络,需要存储数以百万计的图片。你会将所有这些数据存储在数据库中吗? – 2012-08-26 19:59:28
存储文件meta i nfo如db中的位置,但同步db和文件系统将是一个问题。
您的问题看起来像是数据类型问题。 MySQL中的BLOB不是很大。尝试将您的表的列数据类型设置为LONGBLOB。
package com.server;
import java.io.*;
import java.sql.*;
import java.util.*;
import java.text.*;
import java.util.regex.*;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.*;
import org.mortbay.jetty.Response;
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.sql.*;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.ServletInputStream.*;
import java.io.PrintWriter;
public class XmlServlet extends HttpServlet {
public void doPost(HttpServletRequest req,HttpServletResponse res)
{
File uploadedFile;
System.out.print("on server");
try{
Class.forName("com.mysql.jdbc.Driver");
Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3308/image","root","root1");
PrintWriter out=res.getWriter();
//out.println("<br>Content type is :: " +contentType);
//to get the content type information from JSP Request Header
String contentType = req.getContentType();
int flag=0;
FileInputStream fis=null;
FileOutputStream fileOut=null;
//here we are checking the content type is not equal to Null and as well as the passed data from mulitpart/form-data is greater than or equal to 0
if ((contentType != null) && (contentType.indexOf("multipart/form-data") >= 0))
{
DataInputStream in = new DataInputStream(req.getInputStream());
//we are taking the length of Content type data
int formDataLength = req.getContentLength();
byte dataBytes[] = new byte[formDataLength];
int byteRead = 0;
int totalBytesRead = 0;
//this loop converting the uploaded file into byte code
while (totalBytesRead < formDataLength) {
byteRead = in.read(dataBytes, totalBytesRead,formDataLength);
totalBytesRead += byteRead;
}
String file = new String(dataBytes);
//for saving the file name
String saveFile = file.substring(file.indexOf("filename=\"") + 10);
saveFile = saveFile.substring(0, saveFile.indexOf("\n"));
out.println("savefiledddd"+saveFile);
int extension_save=saveFile.lastIndexOf("\"");
String extension_saveName=saveFile.substring(extension_save);
//Here we are invoking the absolute path out of the encrypted data
saveFile = saveFile.substring(saveFile.lastIndexOf("\\")+ 1,saveFile.indexOf("\""));
int lastIndex = contentType.lastIndexOf("=");
String boundary = contentType.substring(lastIndex + 1,contentType.length());
int pos;
//extracting the index of file
pos = file.indexOf("filename=\"");
pos = file.indexOf("\n", pos) + 1;
pos = file.indexOf("\n", pos) + 1;
pos = file.indexOf("\n", pos) + 1;
int boundaryLocation = file.indexOf(boundary, pos) - 4;
int startPos = ((file.substring(0, pos)).getBytes()).length;
int endPos = ((file.substring(0, boundaryLocation)).getBytes()).length;
out.println("savefile"+saveFile);
int file_No=22;
uploadedFile=new File("./war/img");
uploadedFile.mkdir();
String kk=uploadedFile.getAbsolutePath();
String pathname_dir=kk+"/"+saveFile;
//String pathname_dir="C:\\Program Files\\Apache Software Foundation\\Tomcat 6.0\\jk\\"+saveFile;
File filepath=new File(pathname_dir);
out.println("filepath_ "+filepath);
fileOut = new FileOutputStream(filepath);
fileOut.write(dataBytes, startPos, (endPos - startPos));
fileOut.flush();
out.println("<h1> your files are saved</h1></body></html>");
out.close();
File database_filename=new File(pathname_dir);
fis=new FileInputStream(database_filename);
int len=(int)database_filename.length();
PreparedStatement ps = conn.prepareStatement("insert into new (image) values (?)");
ps.setBinaryStream(1,fis,len);
ps.executeUpdate();
ps.close();
flag=1;
}
if(flag==1)
{
fileOut.close();
fis.close();
}
}catch(Exception e)
{
System.out.println("Exception Due to"+e);
e.printStackTrace();
}
}
}
这是一个服务器代码。通过该代码,您可以上传存储在数据库中的任何文件,并将该文件存储在服务器端的(img)文件夹中。通过使用您可以访问该文件的参考。
你会得到什么异常? – soulcheck 2011-11-04 08:50:54