java上传图片或者文件

时间:2021-10-30 04:45:01

package com.pat.postrequestemulator;

import java.io.BufferedReader;

import java.io.DataInputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.io.Serializable;

import java.net.HttpURLConnection;

import java.net.URL;

import java.util.ArrayList;

public class PostRequestEmulator

{

public static void main(String[] args)throws Exception

{

// 设定服务地址

String serverUrl ="http://127.0.0.1:8080/test/upload";

// 设定要上传的普通Form Field及其对应的value

ArrayList<FormFieldKeyValuePair>ffkvp = new ArrayList<FormFieldKeyValuePair>();

ffkvp.add(new FormFieldKeyValuePair("tasktype", "1"));

ffkvp.add(new FormFieldKeyValuePair("dataname", "zhangsan"));

// 设定要上传的文件

ArrayList<UploadFileItem>ufi = new ArrayList<UploadFileItem>();

ufi.add(new UploadFileItem("upload3", "C:\\124038.jpg"));

// ufi.add(new UploadFileItem("upload2", "E:\\full.jpg"));

// ufi.add(new UploadFileItem("upload3", "E:\\dyz.txt"));

HttpPostEmulator hpe = new HttpPostEmulator();

String response =hpe.sendHttpPostRequest(serverUrl, ffkvp, ufi);

System.out.println("Responsefrom server is: " + response);

}

}

class HttpPostEmulator

{

//每个post参数之间的分隔。随意设定,只要不会和其他的字符串重复即可。

private static final String BOUNDARY ="----------HV2ymHFg03ehbqgZCaKO6jyH";

public String sendHttpPostRequest(String serverUrl,

ArrayList<FormFieldKeyValuePair>generalFormFields,

ArrayList<UploadFileItem>filesToBeUploaded) throws Exception

{

// 向服务器发送post请求

URL url = new URL(serverUrl/*"http://127.0.0.1:8080/test/upload"*/);
HttpURLConnection connection= (HttpURLConnection) url.openConnection();
// 发送POST请求必须设置如下两行
connection.setDoOutput(true);
connection.setDoInput(true);
connection.setUseCaches(false);
connection.setRequestMethod("POST");
connection.setRequestProperty("Connection","Keep-Alive");
connection.setRequestProperty("Charset","UTF-8");
connection.setRequestProperty("Content-Type","multipart/form-data; boundary=" + BOUNDARY);
// 头
String boundary = BOUNDARY;
// 传输内容
StringBuffer contentBody =new StringBuffer("--" + BOUNDARY);
// 尾
String endBoundary ="\r\n--" + boundary + "--\r\n";
OutputStream out =connection.getOutputStream();
// 1. 处理文字形式的POST请求
for(FormFieldKeyValuePair ffkvp : generalFormFields)
{
contentBody.append("\r\n")
.append("Content-Disposition: form-data; name=\"")
.append(ffkvp.getKey() + "\"")
.append("\r\n")
.append("\r\n")
.append(ffkvp.getValue())
.append("\r\n")
.append("--")
.append(boundary);

}
String boundaryMessage1 =contentBody.toString();
out.write(boundaryMessage1.getBytes("utf-8"));
// 2. 处理文件上传
for(UploadFileItem ufi :filesToBeUploaded)
{
contentBody = new StringBuffer();
contentBody.append("\r\n")
.append("Content-Disposition:form-data; name=\"")
.append(ufi.getFormFieldName() +"\"; ") // form中field的名称
.append("filename=\"")
.append(ufi.getFileName() +"\"") //上传文件的文件名,包括目录
.append("\r\n")
.append("Content-Type:application/octet-stream")
.append("\r\n\r\n");
String boundaryMessage2 = contentBody.toString();
out.write(boundaryMessage2.getBytes("utf-8"));
// 开始真正向服务器写文件
File file = new File(ufi.getFileName());
DataInputStream dis= new DataInputStream(new FileInputStream(file));
int bytes = 0;
byte[] bufferOut =new byte[(int) file.length()];
bytes =dis.read(bufferOut);
out.write(bufferOut,0, bytes);
dis.close();
contentBody.append("------------HV2ymHFg03ehbqgZCaKO6jyH");
String boundaryMessage = contentBody.toString();
out.write(boundaryMessage.getBytes("utf-8"));
//System.out.println(boundaryMessage);

}
out.write("------------HV2ymHFg03ehbqgZCaKO6jyH--\r\n".getBytes("UTF-8"));
// 3. 写结尾
out.write(endBoundary.getBytes("utf-8"));
out.flush();
out.close();
// 4. 从服务器获得回答的内容
String strLine="";
String strResponse ="";
InputStream in =connection.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(in,"utf8"));

while((strLine =reader.readLine()) != null)
{
strResponse +=strLine +"\n";
}
//System.out.print(strResponse);
return strResponse;

}

}

class FormFieldKeyValuePair implements Serializable

{

private static final long serialVersionUID = 1L;
// The form field used for receivinguser's input,
// such as "username" in "<inputtype="text" name="username"/>"
private String key;
// The value entered by user in thecorresponding form field,
// such as "Patrick" the abovementioned formfield "username"
private String value;
public FormFieldKeyValuePair(String key, String value)
{
this.key = key;
this.value = value;
}
public String getKey()
{
return key;
}
public void setKey(String key)
{
this.key = key;
}
public String getValue()
{
return value;
}
public void setValue(String value)
{
this.value = value;
}

}

class UploadFileItem implements Serializable
{
private static final long serialVersionUID = 1L;
// The form field name in a form used foruploading a file,
// such as "upload1" in "<inputtype="file" name="upload1"/>"
private String formFieldName;
// File name to be uploaded, thefileName contains path,
// such as "E:\\some_file.jpg"
private String fileName;
public UploadFileItem(String formFieldName, String fileName)
{
this.formFieldName =formFieldName;
this.fileName = fileName;
}
public String getFormFieldName()
{
return formFieldName;
}
public void setFormFieldName(String formFieldName)
{
this.formFieldName =formFieldName;
}
public String getFileName()
{
return fileName;
}
public void setFileName(String fileName)
{
this.fileName = fileName;
}

}