Java examples for File Path IO:File Operation
diff File
/*//from ww w.j av a 2 s. co m * Copyright (c) 2015. Philip DeCamp * Released under the BSD 2-Clause License * http://opensource.org/licenses/BSD-2-Clause */ //package com.java2s; import java.io.*; import java.nio.ByteBuffer; public class Main { public static boolean diff(File f1, File f2) throws IOException { if (f1 != null && !f1.exists()) f1 = null; if (f2 != null && !f2.exists()) f2 = null; if (f1 == f2 || f1 != null && f1.equals(f2)) return false; if (f1 == null) return f2 != null && f2.length() != 0; if (f2 == null) return f1 != null && f1.length() != 0; long len = f1.length(); if (len != f2.length()) return true; DataInputStream s1 = new DataInputStream(new BufferedInputStream( new FileInputStream(f1))); DataInputStream s2 = new DataInputStream(new BufferedInputStream( new FileInputStream(f2))); long p = 0; for (; p < len - 7; p += 8) { if (s1.readLong() != s2.readLong()) return true; } for (; p < len; p++) { if (s1.read() != s2.read()) return true; } s1.close(); s2.close(); return false; } public static boolean diff(File f1, ByteBuffer b2) throws IOException { if (f1 != null && !f1.exists()) f1 = null; if (b2 != null) b2 = b2.slice(); if (f1 == null) return b2 != null && b2.remaining() != 0; if (b2 == null) return f1 != null && f1.length() != 0; if (f1.length() != b2.remaining()) return true; DataInputStream s1 = new DataInputStream(new BufferedInputStream( new FileInputStream(f1))); final int len = b2.capacity(); int p = 0; for (; p < len - 7; p += 8) { if (s1.readLong() != b2.getLong()) return true; } for (; p < len; p++) { if (s1.read() != (b2.get() & 0xFF)) return true; } s1.close(); return false; } public static boolean diff(ByteBuffer b1, ByteBuffer b2) throws IOException { if (b1 == b2 || b1 != null && b1.equals(b2)) return false; if (b1 == null) return b2 != null && b2.remaining() != 0; if (b2 == null) return b1 != null && b1.remaining() != 0; b1 = b1.slice(); b2 = b2.slice(); int len = b1.capacity(); if (len != b2.capacity()) return true; int p = 0; for (; p < len - 7; p += 8) if (b1.getLong() != b2.getLong()) return true; for (; p < len; p++) if (b1.get() != b2.get()) return true; return false; } }