1 /* 2 * Copyright (C) 2013 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.documentsui.model; 18 19 import static com.android.documentsui.Shared.TAG; 20 21 import android.os.BadParcelableException; 22 import android.os.Parcel; 23 import android.util.Log; 24 25 import java.io.ByteArrayInputStream; 26 import java.io.ByteArrayOutputStream; 27 import java.io.DataInputStream; 28 import java.io.DataOutputStream; 29 import java.io.IOException; 30 31 public class DurableUtils { 32 public static <D extends Durable> byte[] writeToArray(D d) throws IOException { 33 final ByteArrayOutputStream out = new ByteArrayOutputStream(); 34 d.write(new DataOutputStream(out)); 35 return out.toByteArray(); 36 } 37 38 public static <D extends Durable> D readFromArray(byte[] data, D d) throws IOException { 39 if (data == null) throw new IOException("Missing data"); 40 final ByteArrayInputStream in = new ByteArrayInputStream(data); 41 d.reset(); 42 try { 43 d.read(new DataInputStream(in)); 44 } catch (IOException e) { 45 d.reset(); 46 throw e; 47 } 48 return d; 49 } 50 51 public static <D extends Durable> byte[] writeToArrayOrNull(D d) { 52 try { 53 return writeToArray(d); 54 } catch (IOException e) { 55 Log.w(TAG, "Failed to write", e); 56 return null; 57 } 58 } 59 60 public static <D extends Durable> D readFromArrayOrNull(byte[] data, D d) { 61 try { 62 return readFromArray(data, d); 63 } catch (IOException e) { 64 Log.w(TAG, "Failed to read", e); 65 return null; 66 } 67 } 68 69 public static <D extends Durable> void writeToParcel(Parcel parcel, D d) { 70 try { 71 parcel.writeByteArray(writeToArray(d)); 72 } catch (IOException e) { 73 throw new BadParcelableException(e); 74 } 75 } 76 77 public static <D extends Durable> D readFromParcel(Parcel parcel, D d) { 78 try { 79 return readFromArray(parcel.createByteArray(), d); 80 } catch (IOException e) { 81 throw new BadParcelableException(e); 82 } 83 } 84 85 public static void writeNullableString(DataOutputStream out, String value) throws IOException { 86 if (value != null) { 87 out.write(1); 88 out.writeUTF(value); 89 } else { 90 out.write(0); 91 } 92 } 93 94 public static String readNullableString(DataInputStream in) throws IOException { 95 if (in.read() != 0) { 96 return in.readUTF(); 97 } else { 98 return null; 99 } 100 } 101 } 102