com.appunite.socketio.SocketIOBase.java Source code

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Here is the source code for com.appunite.socketio.SocketIOBase.java

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/*
 * Copyright (C) 2012 Jacek Marchwicki <jacek.marchwicki@gmail.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License
 */

package com.appunite.socketio;

import static com.google.common.base.Preconditions.checkArgument;

import java.io.IOException;
import java.util.HashSet;
import java.util.NoSuchElementException;
import java.util.StringTokenizer;

import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;

import android.net.Uri;
import android.text.TextUtils;

import com.appunite.socketio.helpers.HTTPUtils;
import com.appunite.socketio.helpers.HTTPUtils.WrongHttpResponseCode;
import com.google.common.base.Optional;
import com.google.common.collect.ImmutableSet;

/**
 * Base class for {@link SocketIO}. Its ask socketIO server for websocket
 * connection.
 * 
 * @author Jacek Marchwicki <jacek.marchwicki@gmail.com>
 * 
 */
abstract class SocketIOBase extends SocketBase {

    private HttpClient mClient = null;
    protected final String mSocketIOUrl;
    private HttpGet mRequest;

    protected static class ConnectionResult {
        String sessionId;
        Uri socketUri;
        Optional<Integer> timeout = null;
        Optional<Integer> heartbeat = null;
    }

    private HttpClient getClient() {
        if (mClient != null)
            return mClient;
        mClient = new DefaultHttpClient();
        return mClient;
    }

    public SocketIOBase(String url, SocketListener listener) {
        super(listener);
        checkArgument(url != null, "Argument should not be null");
        this.mSocketIOUrl = url;
    }

    private Optional<Integer> getIntOrAbsetFromString(String str) throws WrongSocketIOResponse {
        if (TextUtils.isEmpty(str)) {
            return Optional.absent();
        } else {
            try {
                return Optional.of(Integer.parseInt(str));
            } catch (NumberFormatException e) {
                throw new WrongSocketIOResponse("Could not parse integer", e);
            }
        }
    }

    private ImmutableSet<String> getTypesFromString(String str) throws WrongSocketIOResponse {
        StringTokenizer st = new StringTokenizer(str, ",");
        HashSet<String> types = new HashSet<String>();
        while (st.hasMoreTokens()) {
            types.add(st.nextToken());
        }
        if (types.isEmpty())
            throw new WrongSocketIOResponse("No transport types in socket response");
        return ImmutableSet.copyOf(types);
    }

    private ConnectionResult connect(String url)
            throws WrongHttpResponseCode, IOException, WrongSocketIOResponse, InterruptedException {
        Uri uri = Uri.parse(url);

        synchronized (mInterruptionLock) {
            if (mInterrupted) {
                throw new InterruptedException();
            }
            mRequest = new HttpGet(url);
        }
        HTTPUtils.setupDefaultHeaders(mRequest);

        HttpResponse response = getClient().execute(mRequest);
        synchronized (mInterruptionLock) {
            if (mRequest.isAborted() || mInterrupted) {
                mRequest = null;
                throw new InterruptedException();
            }
            mRequest = null;
        }
        if (response.getStatusLine().getStatusCode() != HttpStatus.SC_OK) {
            throw new WrongHttpResponseCode(response);
        }

        String responseStr = HTTPUtils.getStringFromResponse(response);
        StringTokenizer responseSplit = new StringTokenizer(responseStr, ":");

        ConnectionResult result = new ConnectionResult();
        try {
            result.sessionId = responseSplit.nextToken();
            if (TextUtils.isEmpty(result.sessionId)) {
                throw new WrongSocketIOResponse("Empty socket io session id");
            }

            result.timeout = getIntOrAbsetFromString(responseSplit.nextToken());
            result.heartbeat = getIntOrAbsetFromString(responseSplit.nextToken());

            ImmutableSet<String> types = getTypesFromString(responseSplit.nextToken());
            if (!types.contains("websocket")) {
                throw new WrongSocketIOResponse("Websocket not found in server response");
            }
        } catch (NoSuchElementException e) {
            throw new WrongSocketIOResponse("Not enough color separated values in response", e);
        }
        result.socketUri = new Uri.Builder().scheme("ws").encodedAuthority(uri.getEncodedAuthority())
                .path(uri.getPath()).appendPath("websocket").appendPath(result.sessionId).build();
        return result;
    }

    @Override
    protected void interrupt() {
        super.interrupt();
        if (mRequest != null) {
            mRequest.abort();
        }
    }

    @Override
    public void runSocket() {
        while (!mInterrupted) {
            try {
                ConnectionResult connect = connect(mSocketIOUrl);
                connectToTransport(connect);
            } catch (WrongHttpResponseCode e) {
                error(e);
            } catch (IOException e) {
                error(e);
            } catch (WrongSocketIOResponse e) {
                error(e);
            } catch (InterruptedException e) {
                // just let die
                continue;
            }
            return;
        }
    }

    abstract void connectToTransport(ConnectionResult connect) throws InterruptedException;

}