/*
* @(#)HttpExample.java 1.21 02/07/25 @(#)
*
* Copyright (c) 1999-2002 Sun Microsystems, Inc. All rights reserved.
* PROPRIETARY/CONFIDENTIAL
* Use is subject to license terms.
*/
/**
* Examples using HttpConnection.
*/
package example.http;
import java.io.*;
import javax.microedition.io.Connector;
import javax.microedition.io.ContentConnection;
import javax.microedition.io.StreamConnection;
import javax.microedition.io.HttpConnection;
import javax.microedition.lcdui.Gauge;
import javax.microedition.lcdui.Form;
import javax.microedition.lcdui.Display;
import javax.microedition.midlet.*;
/**
* sample http example MIDlet.
*/
public class HttpExample extends MIDlet implements Runnable {
/** example URL for HTTP GET */
String url = "http://www.yahoo.com/";
/** string buffer for assembling HTTP requests. */
StringBuffer buffer = new StringBuffer();
/** user interface component for displaying network progress. */
Gauge gauge;
/** user interface screen for displaying progress gauge. */
Form form;
/**
* Create the progress form and gauge.
* This program is not interactive, it will exit when done.
*/
public HttpExample() {
gauge = new Gauge("Progress", false, 10, 0);
form = new Form("Progress");
form.append(gauge);
Display.getDisplay(this).setCurrent(form);
}
/**
* Start a thread to run the examples.
*/
public void startApp() {
new Thread(this).start();
}
/**
* Run the examples.
*/
public void run() {;
try {
gauge.setLabel("Get using ContentConnection");
gauge.setValue(2);
getViaContentConnection(url);
gauge.setLabel("Get using StreamConnection");
gauge.setValue(4);
getViaStreamConnection(url);
gauge.setLabel("Get using HttpConnection");
gauge.setValue(6);
getViaHttpConnection(url);
gauge.setLabel("Post using HttpConnection");
gauge.setValue(8);
postViaHttpConnection(url);
} catch (Exception e) {
System.out.println(e);
e.printStackTrace();
}
gauge.setValue(10);
notifyDestroyed();
}
/**
* Pause, discontinue with the http tests
*/
public void pauseApp() {
}
/**
* Destroy must cleanup everything. The thread is signaled
* to stop and no result is produced.
* @param unconditional true if forced shutdown.
*/
public void destroyApp(boolean unconditional) {
}
/**
* Simple read of a url using StreamConnection.
* No HTTP specific behavior is needed or used.
* <p>
* Connector.open is used to open url and a StreamConnection is returned.
* From the StreamConnection the InputStream is opened.
* It is used to read every character until end of file (-1).
* If an exception is thrown the connection and stream is closed.
* @param url the URL to process.
*/
void getViaStreamConnection(String url) throws IOException {
StreamConnection c = null;
InputStream s = null;
try {
c = (StreamConnection)Connector.open(url);
s = c.openInputStream();
buffer.setLength(0);
int ch;
while ((ch = s.read()) != -1) {
process((byte)ch);
}
} finally {
if (s != null)
s.close();
if (c != null)
c.close();
}
}
/**
* Simple read of a url using ContentConnection.
* No HTTP specific behavior is needed or used.
* <p>
* Connector.open is used to open url and a ContentConnection is returned.
* The ContentConnection may be able to provide the length.
* If the length is available, it is used to read the data in bulk.
* From the StreamConnection the InputStream is opened.
* It is used to read every character until end of file (-1).
* If an exception is thrown the connection and stream is closed.
* @param url the URL to process.
*/
void getViaContentConnection(String url) throws IOException {
ContentConnection c = null;
InputStream is = null;
try {
c = (ContentConnection)Connector.open(url);
is = c.openInputStream();
buffer.setLength(0);
int len = (int)c.getLength();
if (len > 0) {
byte[] data = new byte[len];
int actual = is.read(data);
process(data);
} else {
int ch;
while ((ch = is.read()) != -1) {
process((byte)ch);
}
}
} finally {
if (is != null)
is.close();
if (c != null)
c.close();
}
}
/**
* Read the HTTP headers and the data using HttpConnection.
* Check the response code to insure successful retrieval.
* <p>
* Connector.open is used to open url and a HttpConnection is returned.
* The HTTP headers are read and processed.
* If the length is available, it is used to read the data in bulk.
* From the HttpConnection the InputStream is opened.
* It is used to read every character until end of file (-1).
* If an exception is thrown the connection and stream is closed.
* @param url the URL to process.
*/
void getViaHttpConnection(String url) throws IOException {
HttpConnection c = null;
InputStream is = null;
OutputStream os = null;
try {
int status = -1;
// Open the connection and check for re-directs
while (true) {
c = (HttpConnection)Connector.open(url);
setRequestHeaders(c);
// Get the status code, causing the connection to be made
status = c.getResponseCode();
if (status == HttpConnection.HTTP_TEMP_REDIRECT ||
status == HttpConnection.HTTP_MOVED_TEMP ||
status == HttpConnection.HTTP_MOVED_PERM) {
// Get the new location and close the connection
url = c.getHeaderField("location");
c.close();
System.out.println("Redirecting to " + url);
} else {
break;
}
}
// Any 500 status number (500, 501) means there was a server error
if ((status == HttpConnection.HTTP_NOT_IMPLEMENTED) ||
(status == HttpConnection.HTTP_VERSION) ||
(status == HttpConnection.HTTP_INTERNAL_ERROR) ||
(status == HttpConnection.HTTP_GATEWAY_TIMEOUT) ||
(status == HttpConnection.HTTP_BAD_GATEWAY)) {
System.err.print("WARNING: Server error status ["+status+"] ");
System.err.println("returned for url ["+url+"]");
if (is != null)
is.close();
if (os != null)
os.close();
if (c != null)
c.close();
return;
}
// Only HTTP_OK (200) means the content is returned.
if (status != HttpConnection.HTTP_OK) {
throw new IOException("Response status not OK ["+status+"]");
}
// Get the ContentType
String type = c.getType();
processType(type);
// open the InputStream
is = c.openInputStream();
buffer.setLength(0);
// Get the length and process the data
int len = (int)c.getLength();
if (len > 0) {
byte[] data = new byte[len];
int actual = is.read(data);
process(data);
} else {
int ch;
while ((ch = is.read()) != -1) {
process((byte)ch);
}
}
} finally {
if (is != null)
is.close();
if (c != null)
c.close();
}
}
/**
* Add request properties for the configuration, profiles,
* and locale of this system.
* @param c current HttpConnection to apply request headers
*/
void setRequestHeaders(HttpConnection c) throws IOException {
String conf = System.getProperty("microedition.configuration");
String prof = System.getProperty("microedition.profiles");
int space = prof.indexOf(' ');
if (space != -1) {
prof = prof.substring(0, space -1);
}
String locale = System.getProperty("microedition.locale");
String ua = "Profile/" + prof +
" Configuration/" + conf;
c.setRequestProperty("User-Agent", ua);
if (locale != null) {
c.setRequestProperty("Content-Language", locale);
}
}
/**
* Post a request with some headers and content to the server and
* process the headers and content.
* <p>
* Connector.open is used to open url and a HttpConnection is returned.
* The request method is set to POST and request headers set.
* A simple command is written and flushed.
* The HTTP headers are read and processed.
* If the length is available, it is used to read the data in bulk.
* From the StreamConnection the InputStream is opened.
* It is used to read every character until end of file (-1).
* If an exception is thrown the connection and stream is closed.
* @param url the URL to process.
*/
void postViaHttpConnection(String url) throws IOException {
int status = 0;
HttpConnection c = null;
InputStream is = null;
OutputStream os = null;
try {
c = (HttpConnection)Connector.open(url);
// Set the request method and headers
c.setRequestMethod(HttpConnection.POST);
c.setRequestProperty("If-Modified-Since",
"29 Oct 1999 19:43:31 GMT");
c.setRequestProperty("User-Agent",
"Profile/MIDP-1.0 Configuration/CLDC-1.0");
c.setRequestProperty("Content-Language", "en-US");
// Getting the output stream may flush the headers
os = c.openOutputStream();
os.write("LIST games\n".getBytes());
os.flush(); // Optional, openInputStream will flush
// Get the status code, causing the connection to be made
status = c.getResponseCode();
// Any 500 status number (500, 501) means there was a server error
if ((status == HttpConnection.HTTP_NOT_IMPLEMENTED) ||
(status == HttpConnection.HTTP_VERSION) ||
(status == HttpConnection.HTTP_INTERNAL_ERROR) ||
(status == HttpConnection.HTTP_GATEWAY_TIMEOUT) ||
(status == HttpConnection.HTTP_BAD_GATEWAY)) {
System.err.print("WARNING: Server error status ["+status+"] ");
System.err.println("returned for url ["+url+"]");
if (is != null)
is.close();
if (os != null)
os.close();
if (c != null)
c.close();
return;
}
// Only HTTP_OK (200) means the content is returned.
if (status != HttpConnection.HTTP_OK) {
throw new IOException("Response status not OK ["+status+"]");
}
// Open the InputStream and get the ContentType
is = c.openInputStream();
String type = c.getType();
processType(type);
// Get the length and process the data
int len = (int)c.getLength();
if (len > 0) {
byte[] data = new byte[len];
int actual = is.read(data);
process(data);
} else {
int ch;
while ((ch = is.read()) != -1) {
process((byte)ch);
}
}
} finally {
if (is != null)
is.close();
if (os != null)
os.close();
if (c != null)
c.close();
}
}
/**
* Process the type.
* @param type that type
*/
void processType(String type) {
}
/**
* Process the data one character at a time.
* @param b one byte of data
*/
void process(byte b) {
buffer.append((char)b);
}
/**
* Process the data from the array.
* @param b an array of bytes.
*/
void process(byte[] b) {
for (int i = 0; i < b.length; i++) {
process(b[i]);
}
}
}
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