代码如下：
public static void dealImage(HttpServletRequest request) throws IOException{
// 1.判断当前request消息实体的总长度
int totalBytes = request.getContentLength();
System.out.println("当前数据总长度:" + totalBytes);
// 2.在消息头类型中找出分解符,例如:boundary=----WebKitFormBoundaryeEYAk4vG4tRKAlB6
String contentType = request.getContentType();
int position = contentType.indexOf("boundary=");
String startBoundary = "--" + contentType.substring(position+"boundary=".length());
String endBoundary = startBoundary + "--";
//将request的输入流读入到bytes中
InputStream inputStream = request.getInputStream();
DataInputStream dataInputStream = new DataInputStream(inputStream);
byte[] bytes = new byte[totalBytes];
dataInputStream.readFully(bytes);
dataInputStream.close();
//将字节读入到字符流中
BufferedReader reader = new BufferedReader(new StringReader(new String(bytes)));
//开始读取reader(分割form表单内的表单域类型:文本或者文件)
//记录当前的读取行对应的bytes;
int temPosition = 0;
boolean flag = false;
int end = 0;
while(true){
//当读取一次文件信息后
if(flag){
bytes = subBytes(bytes, end, totalBytes);
temPosition = 0;
reader = new BufferedReader(new StringReader(new String(bytes)));
}
//读取一行的信息:------WebKitFormBoundary5R7esAd459uwQsd5,即:lastBoundary
String str = reader.readLine();
System.out.println("this line is:" + str);
//换行算两个字符
temPosition += str.getBytes().length + 2;
//endBoundary:结束
if(str==null||str.equals(endBoundary)){
break;
}
//表示头信息的开始(一个标签,input,select等)
if(str.startsWith(startBoundary)){
//判断当前头对应的表单域类型
str = reader.readLine(); //读取当前头信息的下一行:Content-Disposition行
temPosition += str.getBytes().length+2;
int position1 = str.indexOf("filename="); //判断是否是文件上传
//such as:Content-Disposition: form-data; name="fileName"; filename="P50611-162907.jpg"
if(position1 == -1){//表示是普通文本域上传
}else{//position1!=-1,表示是文件上传
//解析当前上传的文件对应的name(input标签的name),以及fieldname:文件名
int position2 = str.indexOf("name=");
//去掉name与filename之间的"和;以及空格
String name = str.substring(position2 + "name=".length() + 1, position1-3);
//去掉两个"
String filename = str.substring(position1 + "filename=".length() + + 1,str.length() - 1);
//读取行,such as:Content-Type: image/jpeg,记录字节数,此处两次换行
temPosition += (reader.readLine().getBytes().length + 4);
end = locateEnd(bytes, temPosition, totalBytes, endBoundary);
String path = request.getSession().getServletContext().getRealPath("/");
DataOutputStream dOutputStream = new DataOutputStream(new FileOutputStream(new File(path + "/"+filename)));
dOutputStream.write(bytes, temPosition, end-temPosition-2);
dOutputStream.close();
flag = true;
}
}
}
}
