Java tutorial
/* * Copyright (C) 2015 The Android Open Source Project * * 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.android.phone.common.mail.internet; import com.android.phone.common.mail.Body; import com.android.phone.common.mail.MessagingException; import com.android.phone.common.mail.TempDirectory; import org.apache.commons.io.IOUtils; import android.util.Base64; import android.util.Base64OutputStream; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.FilterInputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; /** * A Body that is backed by a temp file. The Body exposes a getOutputStream method that allows * the user to write to the temp file. After the write the body is available via getInputStream * and writeTo one time. After writeTo is called, or the InputStream returned from * getInputStream is closed the file is deleted and the Body should be considered disposed of. */ public class BinaryTempFileBody implements Body { private File mFile; /** * An alternate way to put data into a BinaryTempFileBody is to simply supply an already- * created file. Note that this file will be deleted after it is read. * @param filePath The file containing the data to be stored on disk temporarily */ public void setFile(String filePath) { mFile = new File(filePath); } public OutputStream getOutputStream() throws IOException { mFile = File.createTempFile("body", null, TempDirectory.getTempDirectory()); mFile.deleteOnExit(); return new FileOutputStream(mFile); } @Override public InputStream getInputStream() throws MessagingException { try { return new BinaryTempFileBodyInputStream(new FileInputStream(mFile)); } catch (IOException ioe) { throw new MessagingException("Unable to open body", ioe); } } @Override public void writeTo(OutputStream out) throws IOException, MessagingException { InputStream in = getInputStream(); Base64OutputStream base64Out = new Base64OutputStream(out, Base64.CRLF | Base64.NO_CLOSE); IOUtils.copy(in, base64Out); base64Out.close(); mFile.delete(); in.close(); } class BinaryTempFileBodyInputStream extends FilterInputStream { public BinaryTempFileBodyInputStream(InputStream in) { super(in); } @Override public void close() throws IOException { super.close(); mFile.delete(); } } }