com.alarexgroup.m2mplf.net.http
Class HttpCommunicator

java.lang.Object
  com.alarexgroup.m2mplf.net.http.HttpCommunicator

public class HttpCommunicator
extends java.lang.Object

Class communicates throughHTTP protocol.

Example: simple request to method GET

HttpCommunicator com = new HttpCommunicator("bearer_type=gprs;access_point=internet;timeout=40");
if (com.openConnection("http://www.google.com",HttpCommunicator.METHOD_GET)==HttpCommunicator.ERROR_CODE_ALL_OK) {
com.addHeaderProperty(Header,Value); //adds parameter to heading
int resp_code = com.sendRequest(); //request sending
byte [] b = com.receiveResponse(); //dates input
com.closeConnection(); //coses conection
} else {
//can't open connection
}

Example: Work with Streams - Streams enables work with bigger dates. Isn't neccessary allocate array with some data size, but because it works with Streams is possible to process dates straightaway.

HttpCommunicator com = new HttpCommunicator("bearer_type=gprs;access_point=internet;timeout=40");
if (com.openConnection("http://www.google.com",HttpCommunicator.METHOD_GET)==HttpCommunicator.ERROR_CODE_ALL_OK){
com.addHeaderProperty(Header,value);
OutputStream os = com.getDataOutputStream();
try {
os.write("Haloo".getBytes()); //sends dates
int error_code = com.sendRequest();
InputStream is = com.getDataInputStream();
is.read(); //receives dates
} catch (IOException ex) {
//handle exception
}
com.closeConnection();
} else {
//is not possible to open conection
}

Field Summary

static int	ERROR_CODE_ALL_OK all right
static int	ERROR_CODE_CONNECTION_NOT_FOUND connection is not possible
static int	ERROR_CODE_INVALID_PARAMETERS wrong URL form or connectionProfile
static int	ERROR_CODE_INVALID_STATE error of HTTP communicator's state
static int	ERROR_CODE_IO_EXCEPTION IO exception
static int	ERROR_CODE_SECURITY_EXCEPTION J2ME security exception
static int	ERROR_CODE_UNKNOWN_ERROR unknown error
static java.lang.String	METHOD_GET HTTP QUERY METHOD - GET
static java.lang.String	METHOD_HEAD HTTP QUERY METHOD - HEAD
static java.lang.String	METHOD_POST HTTP QUERY METHOD - POST
static int	STATE_CLOSED communicator logged off
static int	STATE_CREATED communicator created
static int	STATE_DATA_RECEIVED Answer received
static int	STATE_DATA_RECEIVING Answer receiving
static int	STATE_DATA_SENDING Data sending
static int	STATE_DATA_SENT data was send
static int	STATE_HEAD_COMPLETED HTTP header finalized
static int	STATE_INIT communicator initialized

Constructor Summary

HttpCommunicator()
Creates new communicatro

HttpCommunicator(java.lang.String connectionProfile)
Creates new communicatro - connectionProfile already set

Method Summary

int	addHeaderProperty(java.lang.String key, java.lang.String value) Appends a parameter to HTTP header.
int	closeConnection() This method closes connection.
java.io.DataInputStream	getDataInputStream() Returns InputStream, which includes answer to HTTP request.
java.io.DataOutputStream	getDataOutputStream() Returns OutputStream for data sending.
int	getErrorCode() Returns error code
java.lang.String	getMethod() Returns HTTP Method
java.lang.String	getURL() Returns URL request
int	openConnection(java.lang.String url, java.lang.String method) Opens connection
byte[]	receiveResponse() This method returns loaded answer as an array of bytes.
int	sendRequest() Completes OutpuStream's content sending and returns HTTP response code
int	sendRequest(byte[] message) Sends array of bytes.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

METHOD_POST

public static final java.lang.String METHOD_POST

HTTP QUERY METHOD - POST

METHOD_GET

public static final java.lang.String METHOD_GET

HTTP QUERY METHOD - GET

METHOD_HEAD

public static final java.lang.String METHOD_HEAD

HTTP QUERY METHOD - HEAD

ERROR_CODE_ALL_OK

public static final int ERROR_CODE_ALL_OK

all right

See Also:

Constant Field Values

ERROR_CODE_CONNECTION_NOT_FOUND

public static final int ERROR_CODE_CONNECTION_NOT_FOUND

connection is not possible

See Also:

Constant Field Values

ERROR_CODE_INVALID_PARAMETERS

public static final int ERROR_CODE_INVALID_PARAMETERS

wrong URL form or connectionProfile

See Also:

Constant Field Values

ERROR_CODE_SECURITY_EXCEPTION

public static final int ERROR_CODE_SECURITY_EXCEPTION

J2ME security exception

See Also:

Constant Field Values

ERROR_CODE_IO_EXCEPTION

public static final int ERROR_CODE_IO_EXCEPTION

IO exception

See Also:

Constant Field Values

ERROR_CODE_INVALID_STATE

public static final int ERROR_CODE_INVALID_STATE

error of HTTP communicator's state

See Also:

Constant Field Values

ERROR_CODE_UNKNOWN_ERROR

public static final int ERROR_CODE_UNKNOWN_ERROR

unknown error

See Also:

Constant Field Values

STATE_CREATED

public static final int STATE_CREATED

communicator created

See Also:

Constant Field Values

STATE_INIT

public static final int STATE_INIT

communicator initialized

See Also:

Constant Field Values

STATE_HEAD_COMPLETED

public static final int STATE_HEAD_COMPLETED

HTTP header finalized

See Also:

Constant Field Values

STATE_DATA_SENDING

public static final int STATE_DATA_SENDING

Data sending

See Also:

Constant Field Values

STATE_DATA_SENT

public static final int STATE_DATA_SENT

data was send

See Also:

Constant Field Values

STATE_DATA_RECEIVING

public static final int STATE_DATA_RECEIVING

Answer receiving

See Also:

Constant Field Values

STATE_DATA_RECEIVED

public static final int STATE_DATA_RECEIVED

Answer received

See Also:

Constant Field Values

STATE_CLOSED

public static final int STATE_CLOSED

communicator logged off

See Also:

Constant Field Values

Constructor Detail

HttpCommunicator

public HttpCommunicator()

Creates new communicatro

HttpCommunicator

public HttpCommunicator(java.lang.String connectionProfile)

Creates new communicatro - connectionProfile already set

Parameters:

connectionProfile - - example: bearer_type=gprs;access_point=internet;username=someone;password=something;timeout=40

Method Detail

openConnection

public int openConnection(java.lang.String url,
                          java.lang.String method)

Opens connection

Parameters:

url - - url example: http://www.google.com

method - - HTTP method - METHOD_GET, METHOD_POST

Returns:

errorCode

See Also:

METHOD_GET, METHOD_POST, METHOD_HEAD

addHeaderProperty

public int addHeaderProperty(java.lang.String key,
                             java.lang.String value)

Appends a parameter to HTTP header. Parameters can only be appended before sending the request/data itself.

Parameters:

key - - name of HTTP parameter

value - - value of HTTP parameter

Returns:

error code

getDataOutputStream

public java.io.DataOutputStream getDataOutputStream()

Returns OutputStream for data sending. If the method was already used, use addHeader() again is not possible.

Returns:

dataoutputstream - null if an error occurred

getDataInputStream

public java.io.DataInputStream getDataInputStream()

Returns InputStream, which includes answer to HTTP request.

Returns:

dataoutpustream - null if error occurred

sendRequest

public int sendRequest()

Completes OutpuStream's content sending and returns HTTP response code

Returns:

HTTP response code

sendRequest

public int sendRequest(byte[] message)

Sends array of bytes. It's possible to use it only ones.

Parameters:

message - - dates

Returns:

HTTP response code

receiveResponse

public byte[] receiveResponse()

This method returns loaded answer as an array of bytes.

Returns:

response

closeConnection

public int closeConnection()

This method closes connection. Next request is possible to create by openConnection()

Returns:

errorcode

getURL

public java.lang.String getURL()

Returns URL request

Returns:

url

getMethod

public java.lang.String getMethod()

Returns HTTP Method

Returns:

method

getErrorCode

public int getErrorCode()

Returns error code

Returns:

error