这是解决问题的两步过程:
- 使用 Struts 2 上传文件
- PostgreSQL Java 教程,查看编写图像部分。
附加说明:在您的操作中收到文件后,您应该使用字节数组数据将其保存在您的OID
字段中。
根据您的评论,这应该是 Struts 1.x 中的方式
在 JSP 中
<html:form action="fileUploadAction" method="post" enctype="multipart/form-data">
File : <html:file property="upload" />
<br />
<html:submit />
</html:form>
在你的行动课上
YourForm uploadForm = (YourForm) form;
FormFile file = null;
try {
file = uploadForm.getFile();
//FormFile#getFileData() returns the byte array containing the file data
//You can use it to save the file in your database and other things you want/need
int id = 9001; //assuming this is a valid id in the mensaje table
MensajeService mensajeService = new MensajeService();
mensajeService.saveFile(id, file.getFileData());
} catch (Exception e) {
//log the errors for maintenance purposes (bugs, fixes, etc)
}
该类MensajeService
将连接到您的 Postgre 数据库并保存文件
public class MensajeService {
public MensajeService() {
}
public void saveFile(int id, byte[] fileData) throws SQLException {
//this is a very simple skeleton, you have to adapt this to
//your needs, the way you're connecting to dabatase, etc...
Connection con = null;
PreparedStatement pstmt = null;
try {
con = ... //get the connection to your postgre db
//Initialize a new transaction
con.setAutoCommit(false);
// Get the Large Object Manager to perform operations with
LargeObjectManager lobj = ((org.postgresql.PGConnection)conn)
.getLargeObjectAPI();
// Create a new large object
int oid = lobj.create(LargeObjectManager.READ | LargeObjectManager.WRITE);
// Open the large object for writing
LargeObject obj = lobj.open(oid, LargeObjectManager.WRITE);
//in the provided example, the code shows a way to get the byte array data
//from the file (using the File and FileInputStream classes)
//you don't need all that because you already have the byte array (good!)
//so you only write the binary data in your LargeObject (OID) object
obj.write(fileData);
//creating the SQL statement to insert the OID
String sql = "INSERT INTO mensaje VALUES (?, ?)";
pstmt = con.prepareStatement(sql);
pstmt.setInt(1, id);
ps.setInt(2, oid);
//
pstmt.setBinaryStream(2, fin, (int) img.length());
//saving the file
pstmt.executeUpdate();
//closing the transaction successfully
con.commit();
} catch (SQLException e) {
//error in the transaction, start a rollback
if (con != null) {
con.rollback();
}
throw e;
} finally {
//don't forget to free the resources after using them
pstmt.close();
con.close();
}
}
}
Struts 1 代码改编自:Uploading a file in struts1。
PostreSQL 代码改编自这里。