Spring实现文件上传功能
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2024-03-31 19:29:46
本篇文章，我们要来做一个spring的文件上传功能：
1. 创建一个maven的web工程，然后配置pom.xml文件，增加依赖：
本篇文章，我们要来做一个spring的文件上传功能：
1. 创建一个maven的web工程，然后配置pom.xml文件，增加依赖：
<dependency> <groupid>org.springframework.boot</groupid> <artifactid>spring-boot-starter-web</artifactid> <version>1.0.2.release</version> </dependency>
2.在webapp目录下的index.jsp文件中输入一个表单：
<html>
<body>
<form method="post" enctype="multipart/form-data"
action="/upload">
file to upload: <input type="file" name="file"><br /> name: <input
type="text" name="name"><br /> <br /> <input type="submit"
value="upload"> press here to upload the file!
</form>
</body>
</html>
这个表单就是我们模拟的上传页面。
3. 编写处理这个表单的controller：
import java.io.bufferedoutputstream;
import java.io.file;
import java.io.fileoutputstream;
import org.springframework.stereotype.controller;
import org.springframework.web.bind.annotation.requestmapping;
import org.springframework.web.bind.annotation.requestmethod;
import org.springframework.web.bind.annotation.requestparam;
import org.springframework.web.bind.annotation.responsebody;
import org.springframework.web.multipart.multipartfile;
@controller
public class fileuploadcontroller {
@requestmapping(value="/upload", method=requestmethod.get)
public @responsebody string provideuploadinfo() {
return "you can upload a file by posting to this same url.";
}
@requestmapping(value="/upload", method=requestmethod.post)
public @responsebody string handlefileupload(@requestparam("name") string name,
@requestparam("file") multipartfile file){
if (!file.isempty()) {
try {
byte[] bytes = file.getbytes();
bufferedoutputstream stream =
new bufferedoutputstream(new fileoutputstream(new file(name + "-uploaded")));
stream.write(bytes);
stream.close();
return "you successfully uploaded " + name + " into " + name + "-uploaded !";
} catch (exception e) {
return "you failed to upload " + name + " => " + e.getmessage();
}
} else {
return "you failed to upload " + name + " because the file was empty.";
}
}
}
4. 然后我们对上传的文件做一些限制，同时编写main方法来启动这个web ：
import org.springframework.boot.springapplication;
import org.springframework.boot.autoconfigure.enableautoconfiguration;
import org.springframework.boot.context.embedded.multipartconfigfactory;
import org.springframework.context.annotation.bean;
import org.springframework.context.annotation.componentscan;
import org.springframework.context.annotation.configuration;
import javax.servlet.multipartconfigelement;
@configuration
@componentscan
@enableautoconfiguration
public class application {
@bean
public multipartconfigelement multipartconfigelement() {
multipartconfigfactory factory = new multipartconfigfactory();
factory.setmaxfilesize("128kb");
factory.setmaxrequestsize("128kb");
return factory.createmultipartconfig();
}
public static void main(string[] args) {
springapplication.run(application.class, args);
}
}
5. 然后访问http://localhost:8080/upload就可以看到页面了。
上面的例子是实现的是单个文件上传的功能，假定我们现在要实现文件批量上传的功能的话，我们只需要简单的修改一下上面的代码就行，考虑到篇幅的问题，下面只是贴出和上面不同的代码，没有贴出的说明和上面一样。：
1. 新增batchupload.jsp文件
<html> <body> <form method="post" enctype="multipart/form-data" action="/batch/upload"> file to upload: <input type="file" name="file"><br /> file to upload: <input type="file" name="file"><br /> <input type="submit" value="upload"> press here to upload the file! </form> </body> </html>
2. 新增batchfileuploadcontroller.java文件：
import org.springframework.stereotype.controller;
import org.springframework.web.bind.annotation.requestmapping;
import org.springframework.web.bind.annotation.requestmethod;
import org.springframework.web.bind.annotation.responsebody;
import org.springframework.web.multipart.multipartfile;
import org.springframework.web.multipart.multiparthttpservletrequest;
import javax.servlet.http.httpservletrequest;
import java.io.bufferedoutputstream;
import java.io.file;
import java.io.fileoutputstream;
import java.util.list;
/**
* created by wenchao.ren on 2014/4/26.
*/
@controller
public class batchfileuploadcontroller {
@requestmapping(value="/batch/upload", method= requestmethod.post)
public @responsebody
string handlefileupload(httpservletrequest request){
list<multipartfile> files = ((multiparthttpservletrequest)request).getfiles("file");
for (int i =0; i< files.size(); ++i) {
multipartfile file = files.get(i);
string name = file.getname();
if (!file.isempty()) {
try {
byte[] bytes = file.getbytes();
bufferedoutputstream stream =
new bufferedoutputstream(new fileoutputstream(new file(name + i)));
stream.write(bytes);
stream.close();
} catch (exception e) {
return "you failed to upload " + name + " => " + e.getmessage();
}
} else {
return "you failed to upload " + name + " because the file was empty.";
}
}
return "upload successful";
}
}
这样一个简单的批量上传文件的功能就ok了，是不是很简单啊。
注意：上面的代码只是为了演示而已，所以编码风格上采取了随性的方式，不建议大家模仿。
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。
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