com.noisepages.nettoyeur.usb.DeviceInfo.java Source code

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Here is the source code for com.noisepages.nettoyeur.usb.DeviceInfo.java

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/*
 * Copyright (C) 2013 Peter Brinkmann (peter.brinkmann@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.noisepages.nettoyeur.usb;

import java.io.IOException;
import java.util.Scanner;

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

import android.hardware.usb.UsbDevice;

/**
 * Support for retrieving human-readable names of USB devices from the web
 * (http://usb-ids.gowdy.us/index.html).
 * 
 * @author Peter Brinkmann (peter.brinkmann@gmail.com)
 */
public class DeviceInfo {

    private final String vendor;
    private final String product;

    /**
     * Synchronously retrieves device info from the web. This method must not be invoked on the main
     * thread as it performs blocking network operations that may cause the app to become
     * unresponsive.
     * 
     * Requires android.permission.INTERNET.
     * 
     * @param device for which to retrieve information
     * @return device info, or null on failure
     */
    public static DeviceInfo retrieveDeviceInfo(UsbDevice device) {
        DeviceInfo info = null;
        try {
            info = retrieveDeviceInfo(device.getVendorId(), device.getProductId());
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return info;
    }

    /**
     * Constructor for default instances of DeviceInfo, populated with numerical IDs rather than
     * human-readable names.
     */
    public DeviceInfo(UsbDevice device) {
        this(asFourDigitHex(device.getVendorId()), asFourDigitHex(device.getProductId()));
    }

    private DeviceInfo(String vendor, String product) {
        this.vendor = vendor;
        this.product = product;
    }

    public String getVendor() {
        return vendor;
    }

    public String getProduct() {
        return product;
    }

    private static String asFourDigitHex(int id) {
        return Integer.toHexString(0x10000 | id).substring(1);
    }

    private static DeviceInfo retrieveDeviceInfo(int vendorId, int productId)
            throws ClientProtocolException, IOException {
        String vendorHex = asFourDigitHex(vendorId);
        String productHex = asFourDigitHex(productId);
        String url = "http://usb-ids.gowdy.us/read/UD/" + vendorHex;
        String vendorName = null;
        String productName = null;
        vendorName = getName(url);
        productName = getName(url + "/" + productHex);
        return (vendorName != null && productName != null) ? new DeviceInfo(vendorName, productName) : null;
    }

    private static String getName(String url) throws ClientProtocolException, IOException {
        HttpClient client = new DefaultHttpClient();
        HttpGet request = new HttpGet(url);
        HttpResponse response = client.execute(request);
        Scanner scanner = new Scanner(response.getEntity().getContent());
        while (scanner.hasNext()) {
            String line = scanner.nextLine();
            int start = line.indexOf("Name:") + 6;
            if (start > 5) {
                int end = line.indexOf("<", start);
                if (end > start) {
                    return line.substring(start, end);
                }
            }
        }
        return null;
    }

    @Override
    public String toString() {
        return vendor + ":" + product;
    }

    @Override
    public int hashCode() {
        return 31 * vendor.hashCode() + product.hashCode();
    }

    @Override
    public boolean equals(Object o) {
        return (o instanceof DeviceInfo) && ((DeviceInfo) o).vendor.equals(vendor)
                && ((DeviceInfo) o).product.equals(product);
    }
}