1 /* 2 * Copyright (C) 2015 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.android.usbtuner; 18 19 import android.util.Log; 20 21 import com.android.usbtuner.data.Channel; 22 23 import java.io.BufferedReader; 24 import java.io.IOException; 25 import java.io.InputStream; 26 import java.io.InputStreamReader; 27 import java.util.ArrayList; 28 import java.util.List; 29 30 /** 31 * Parses plain text formatted scan files, which contain the list of channels. 32 */ 33 public class ChannelScanFileParser { 34 private static final String TAG = "ChannelScanFileParser"; 35 36 public static final class ScanChannel { 37 public final int type; 38 public final int frequency; 39 public final String modulation; 40 public final String filename; 41 42 public static ScanChannel forTuner(int frequency, String modulation) { 43 return new ScanChannel(Channel.TYPE_TUNER, frequency, modulation, null); 44 } 45 46 public static ScanChannel forFile(int frequency, String filename) { 47 return new ScanChannel(Channel.TYPE_FILE, frequency, "file:", filename); 48 } 49 50 private ScanChannel(int type, int frequency, String modulation, String filename) { 51 this.type = type; 52 this.frequency = frequency; 53 this.modulation = modulation; 54 this.filename = filename; 55 } 56 } 57 58 /** 59 * Parses a given scan file and returns the list of {@link ScanChannel} objects. 60 * 61 * @param is {@link InputStream} of a scan file. Each line matches one channel. 62 * The line format of the scan file is as follows:<br> 63 * "A <frequency> <modulation>". 64 * @return a list of {@link ScanChannel} objects parsed 65 */ 66 public static List<ScanChannel> parseScanFile(InputStream is) { 67 BufferedReader in = new BufferedReader(new InputStreamReader(is)); 68 String line; 69 List<ScanChannel> scanChannelList = new ArrayList<>(); 70 try { 71 while ((line = in.readLine()) != null) { 72 if (line.isEmpty()) { 73 continue; 74 } 75 if (line.charAt(0) == '#') { 76 // Skip comment line 77 continue; 78 } 79 String[] tokens = line.split("\\s+"); 80 if (tokens.length != 3) { 81 continue; 82 } 83 if (!tokens[0].equals("A")) { 84 // Only support ATSC 85 continue; 86 } 87 scanChannelList.add(ScanChannel.forTuner(Integer.parseInt(tokens[1]), tokens[2])); 88 } 89 } catch (IOException e) { 90 Log.e(TAG, "error on parseScanFile()", e); 91 } 92 return scanChannelList; 93 } 94 } 95
