1 /* 2 * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 /* 25 * @test 26 * @bug 4393174 27 * @summary Checks that ImageIO.write(..., ..., File) truncates the file 28 */ 29 30 import java.awt.image.BufferedImage; 31 import java.io.File; 32 import java.io.FileOutputStream; 33 34 import javax.imageio.ImageIO; 35 36 public class ImageIOWriteFile { 37 38 public static void main(String[] args) { 39 long length0 = -1L; 40 long length1 = -1L; 41 42 try { 43 BufferedImage bi = 44 new BufferedImage(1, 1, BufferedImage.TYPE_INT_RGB); 45 46 File outFile = File.createTempFile("imageiowritefile", ".tmp"); 47 48 // Write image to an empty file 49 outFile.delete(); 50 ImageIO.write(bi, "png", outFile); 51 length0 = outFile.length(); 52 53 // Write a larger file full of junk 54 outFile.delete(); 55 FileOutputStream fos = new FileOutputStream(outFile); 56 for (int i = 0; i < length0*2; i++) { 57 fos.write(1); 58 } 59 fos.close(); 60 61 // Write image again 62 ImageIO.write(bi, "png", outFile); 63 length1 = outFile.length(); 64 65 outFile.delete(); 66 } catch (Exception e) { 67 e.printStackTrace(); 68 throw new RuntimeException("Unexpected exception!"); 69 } 70 71 if (length0 == 0) { 72 throw new RuntimeException("File length is zero!"); 73 } 74 if (length1 != length0) { 75 throw new RuntimeException("File length changed!"); 76 } 77 } 78 }