outputstream

问题 I know this has been answered 10,000+ times. I have been reading and testing recommendations for over an hour without any progress. In the code below, the request body is always empty. URL url = new URL("[REMOVED]"); HttpURLConnection conn = (HttpURLConnection)url.openConnection(); conn.setRequestProperty("Authorization", "Bearer [REMOVED]"); conn.setRequestMethod("POST"); conn.setRequestProperty("Content-Type","application/json"); conn.setDoOutput(true); conn.setDoInput(true);

问题 The below code is quoted from : http://examples.javacodegeeks.com/core-java/io/fileoutputstream/java-io-fileoutputstream-example/ Although the OutputStream is an abstract method, at the below code, OutputStream object is used for writing into the file. Files.newOutputStream(filepath)) returns OutputStream. Then, the type of out is OutputStream, and out references OutputStream. How can this be possible while OutputStream is an abstract class? package com.javacodegeeks.core.io.outputstream;

问题 I'm trying to make a client/socket program that involves sending a string from the client (to identify which key should be used) to the server, the server sends back a key in byte form, the client then sends a request for a file in string form, the server sends the requested file to the user which can be decrypted with they key. I understand the cryptology aspects, I'm hung up on how to differentiate between sending bytes, string or a file to and from a server. I understand how to send a

问题 I need to store data into files inside .jar file and read it again. I know that I can use Class.getResourceAsStream() method but it returns an InputStream that I can read from. But I look for a way to write. 回答1: I need to store data into files inside .jar file and read it again No you don't. Instead store the 'default' file inside the Jar. If it is changed, store the altered file in another place. One common place is a sub-directory of user.home . When checking for the file, first check the

问题 I'm looking for something that does the same thing than outputStream.write() but which will accept an array of int. Actually, I'm using this one : outputStream.write() but this one accepts only byte , byte[] or int . I could use the byte[] but the values I want to send are [255,44,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,255] so I can use the byte[] because there range are only from -127 to 127 :/ It's to send a command on a Port_Com which accept only packet of 19 bytes and must be start and end with

问题 Within a SpringBoot app, I am attempting to return images via a Response object's outputBuffer, via: try { response.setContentType("image/png"); InputStream in = new FileInputStream(pathToFile); IOUtils.copy(in, response.getOutputStream()); } catch (Exception e){ ... } This works fine, unless the image is less than 8kb , in which case it just returns nothing. Can anyone tell me why being less than 8kb would cause the Response to actually return zero data (and - crucially - how to remedy this)

问题 I'm trying to execute myfile.jar using another java program which as follows. When the myfile.jar is executed standalone in console, it will as two questions: Start the load process (y/n)? Start the patch process (y/n)? I will pass y to 1st and n to 2nd question. The same thing I'm trying to do using the following java program and it successfully passes answer to the 1st question, but waiting at the 2nd question. ProcessBuilder pb = new ProcessBuilder("java", "-jar", "myfile.jar", "arg1"); pb

问题 I have problems sending data from java to a (linux)-subprocess created by ProcessBuilder/Process . A shell-only based basic example would look like as follows and works fine. echo "hello world" | cat - >/tmp/receive.dat Now, I want to substituted the echo "hello world" by a java program which should internally create a new process (the cat - >/tmp/receive.dat ) and then send data to it. I tried the following, but the file /tmp/receive.dat remains untouched: String[] cmdArray = { "/bin/cat", "

问题 How do I convert the FileWriter to OutputStreamWriter ? This is the directory that I stored the .java files. src/RX/example.java where RX is the package name. I inserted all the images and text files inside the same directory. Here is my working code with FileWriter. try { StringReader stringReader = new StringReader("Save this Message"); BufferedReader bufferedReader = new BufferedReader(stringReader); FileWriter fileWriter = new FileWriter("src/RX/rxUser.txt"); BufferedWriter bufferedWriter

问题 I would like to roughly monitor the progress of a file upload. I know that I can override the MultipartEntity and make the writeTo(OutputStream out) method write to a FilterOutputStream class that I created to wrap the default InputStream. For full details on how I did that, see my answer here. However, upon closer inspection this counts every byte sent twice! I went to the documentation to see what was up. Looks like FilterOutputStream's write(byte[], int, int) method simply calls the