How can i send a strin using getOutputStream method. It can only send byte as they mentioned. So far I can send a byte. but not a string value.
public void sendToPort() throws IOException {
Socket socket = null;
try {
socket = new Socket("ip address", 4014);
socket.getOutputStream().write(2); // have to insert the string
} catch (UnknownHostException e) {
System.err.print(e);
} finally {
socket.close();
}
}
Thanks in advance
How about using PrintWriter:
OutputStream outstream = socket .getOutputStream();
PrintWriter out = new PrintWriter(outstream);
String toSend = "String to send";
out.print(toSend );
EDIT: Found my own answer and saw an improvement was discussed but left out. Here is a better way to write strings using OutputStreamWriter:
// Use encoding of your choice
Writer out = new BufferedWriter(new OutputStreamWriter(
new FileOutputStream(fileDir), "UTF8"));
// append and flush in logical chunks
out.append(toSend).append("\n");
out.append("appending more before flushing").append("\n");
out.flush();
OutputStreamWriter and write is as simple, allows you to specify the encoding, and avoids the exception nastiness.Use OutputStreamWriter class to achieve what you want
public void sendToPort() throws IOException {
Socket socket = null;
OutputStreamWriter osw;
String str = "Hello World";
try {
socket = new Socket("ip address", 4014);
osw =new OutputStreamWriter(socket.getOutputStream(), "UTF-8");
osw.write(str, 0, str.length());
} catch (IOException e) {
System.err.print(e);
} catch (UnknownHostException e) {
System.err.print(e);
} finally {
socket.close();
}
}
Two options:
OutputStream in an OutputStreamWriter, so you can then send the stringString.getBytes(encoding)Note that in both cases you should specify the encoding explicitly, e.g. "UTF-8" - that avoids it just using the platform default encoding (which is almost always a bad idea).
This will just send the character data itself though - if you need to send several strings, and the other end needs to know where each one starts and ends, you'll need a more complicated protocol. If it's Java on both ends, you could use DataInputStream and DataOutputStream; otherwise you may want to come up with your own protocol (assuming it isn't fixed already).
if you have a simple string you can do
socket.getOutputStream().write("your string".getBytes("US-ASCII")); // or UTF-8 or any other applicable encoding...
You can use OutputStreamWriter like this:
OutputStreamWriter out = new OutputStreamWriter(socket.getOutputStream());
out.write("SomeString", 0, "SomeString".length);
You may want to specify charset, such as "UTF-8" "UTF-16"......
OutputStreamWriter out = new OutputStreamWriter(socket.getOutputStream(),
"UTF-8");
out.write("SomeString", 0, "SomeString".length);
Or PrintStream:
PrintStream out = new PrintStream(socket.getOutputStream());
out.println("SomeString");
Or DataOutputStream:
DataOutputStream out = new DataOutputStream(socket.getOutputStream());
out.writeBytes("SomeString");
out.writeChars("SomeString");
out.writeUTF("SomeString");
Or you can find more Writers and OutputStreams in
The java.io package
public void sendToPort() throws IOException {
DataOutputStream dataOutputStream = null;
Socket socket = null;
try {
socket = new Socket("ip address", 4014);
dataOutputStream = new DataOutputStream(socket.getOutputStream());
dataOutputStream.writeUTF("2"); // have to insert the string
} catch (UnknownHostException e) {
System.err.print(e);
} finally {
if(socket != null) {
socket.close();
}
if(dataOutputStream != null) {
dataOutputStream.close();
}
}
}
NOTE: You will need to use DataInputStream readUTF() method from the receiving side.
NOTE: you have to check for null in the "finally" caluse; otherwise you will run into NullPointerException later on.
I see a bunch of very valid solutions in this post. My favorite is using Apache Commons to do the write operation:
IOUtils.write(CharSequence, OutputStream, Charset)
basically doing for instance:
IOUtils.write("Your String", socket.getOutputStream(), "UTF-8")
and catching the appropriate exceptions. If you're trying to build some sort of protocol you can look into the Apache commons-net library for some hints.
You can never go wrong with that. And there are many other useful methods and classes in Apache commons-io that will save you time.
Old posts, but I can see same defect in most of the posts. Before closing the socket, flush the stream. Like in @Josnidhin's answer:
public void sendToPort() throws IOException {
Socket socket = null;
OutputStreamWriter osw;
String str = "Hello World";
try {
socket = new Socket("ip address", 4014);
osw =new OutputStreamWriter(socket.getOutputStream(), 'UTF-8');
osw.write(str, 0, str.length());
osw.flush();
} catch (IOException e) {
System.err.print(e);
} finally {
socket.close();
}
}
