1 /* 2 * Copyright (C) 2011 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 libcore.io; 18 19 import java.io.IOException; 20 import java.net.SocketException; 21 22 /** 23 * A checked exception thrown when {@link Os} methods fail. This exception contains the native 24 * errno value, for comparison against the constants in {@link OsConstants}, should sophisticated 25 * callers need to adjust their behavior based on the exact failure. 26 */ 27 public final class ErrnoException extends Exception { 28 private final String functionName; 29 public final int errno; 30 ErrnoException(String functionName, int errno)31 public ErrnoException(String functionName, int errno) { 32 this.functionName = functionName; 33 this.errno = errno; 34 } 35 ErrnoException(String functionName, int errno, Throwable cause)36 public ErrnoException(String functionName, int errno, Throwable cause) { 37 super(cause); 38 this.functionName = functionName; 39 this.errno = errno; 40 } 41 42 /** 43 * Converts the stashed function name and errno value to a human-readable string. 44 * We do this here rather than in the constructor so that callers only pay for 45 * this if they need it. 46 */ getMessage()47 @Override public String getMessage() { 48 String errnoName = OsConstants.errnoName(errno); 49 if (errnoName == null) { 50 errnoName = "errno " + errno; 51 } 52 String description = Libcore.os.strerror(errno); 53 return functionName + " failed: " + errnoName + " (" + description + ")"; 54 } 55 rethrowAsIOException()56 public IOException rethrowAsIOException() throws IOException { 57 IOException newException = new IOException(getMessage()); 58 newException.initCause(this); 59 throw newException; 60 } 61 rethrowAsSocketException()62 public SocketException rethrowAsSocketException() throws SocketException { 63 throw new SocketException(getMessage(), this); 64 } 65 } 66