Java tutorial
/** * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You 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.github.houbin217jz.thumbnail; import java.io.File; import java.io.IOException; import java.nio.file.FileVisitOption; import java.nio.file.FileVisitResult; import java.nio.file.Files; import java.nio.file.LinkOption; import java.nio.file.Path; import java.nio.file.Paths; import java.nio.file.SimpleFileVisitor; import java.nio.file.attribute.BasicFileAttributes; import java.util.EnumSet; import net.coobird.thumbnailator.Thumbnails; import net.coobird.thumbnailator.Thumbnails.Builder; import org.apache.commons.cli.CommandLine; import org.apache.commons.cli.CommandLineParser; import org.apache.commons.cli.HelpFormatter; import org.apache.commons.cli.Options; import org.apache.commons.cli.ParseException; import org.apache.commons.cli.PosixParser; /** * ?Sample * ??Java 7 ? * Jar???????? * * ?Library: * Thumbnailator: https://code.google.com/p/thumbnailator * Common CLI: http://commons.apache.org/proper/commons-cli * @author Bin Hou * */ public class Thumbnail { public static void main(String[] args) { Options options = new Options(); options.addOption("s", "src", true, "????????????"); options.addOption("d", "dst", true, ""); options.addOption("r", "ratio", true, "/??, 30%???0.3????????"); options.addOption("w", "width", true, "(px)"); options.addOption("h", "height", true, "?(px)"); options.addOption("R", "recursive", false, "???????"); HelpFormatter formatter = new HelpFormatter(); String formatstr = "java -jar thumbnail.jar " + "[-s/--src <path>] " + "[-d/--dst <path>] " + "[-r/--ratio double] " + "[-w/--width integer] " + "[-h/--height integer] " + "[-R/--recursive] "; CommandLineParser parser = new PosixParser(); CommandLine cmd = null; try { cmd = parser.parse(options, args); } catch (ParseException e1) { formatter.printHelp(formatstr, options); return; } final Path srcDir, dstDir; final Integer width, height; final Double ratio; // if (cmd.hasOption("s")) { srcDir = Paths.get(cmd.getOptionValue("s")).toAbsolutePath(); } else { srcDir = Paths.get("").toAbsolutePath(); //?? } // if (cmd.hasOption("d")) { dstDir = Paths.get(cmd.getOptionValue("d")).toAbsolutePath(); } else { formatter.printHelp(formatstr, options); return; } if (!Files.exists(srcDir, LinkOption.NOFOLLOW_LINKS) || !Files.isDirectory(srcDir, LinkOption.NOFOLLOW_LINKS)) { System.out.println("[" + srcDir.toAbsolutePath() + "]??????"); return; } if (Files.exists(dstDir, LinkOption.NOFOLLOW_LINKS)) { if (!Files.isDirectory(dstDir, LinkOption.NOFOLLOW_LINKS)) { //???????? System.out.println("????????"); return; } } else { //???????? try { Files.createDirectories(dstDir); } catch (IOException e) { e.printStackTrace(); return; } } //?? if (cmd.hasOption("w") && cmd.hasOption("h")) { try { width = Integer.valueOf(cmd.getOptionValue("width")); height = Integer.valueOf(cmd.getOptionValue("height")); } catch (NumberFormatException e) { System.out.println("??????"); return; } } else { width = null; height = null; } //? if (cmd.hasOption("r")) { try { ratio = Double.valueOf(cmd.getOptionValue("r")); } catch (NumberFormatException e) { System.out.println("?????"); return; } } else { ratio = null; } if (width != null && ratio != null) { System.out.println("??????????????"); return; } if (width == null && ratio == null) { System.out.println("????????????"); return; } // int maxDepth = 1; if (cmd.hasOption("R")) { maxDepth = Integer.MAX_VALUE; } try { //Java 7 ??@see http://docs.oracle.com/javase/jp/7/api/java/nio/file/Files.html Files.walkFileTree(srcDir, EnumSet.of(FileVisitOption.FOLLOW_LINKS), maxDepth, new SimpleFileVisitor<Path>() { @Override public FileVisitResult visitFile(Path path, BasicFileAttributes basicFileAttributes) throws IOException { //???&??? String filename = path.getFileName().toString().toLowerCase(); if (filename.endsWith(".jpg") || filename.endsWith(".jpeg")) { //Jpeg?? /* * relative??: * rootPath: /a/b/c/d * filePath: /a/b/c/d/e/f.jpg * rootPath.relativize(filePath) = e/f.jpg */ /* * resolve?? * rootPath: /a/b/c/output * relativePath: e/f.jpg * rootPath.resolve(relativePath) = /a/b/c/output/e/f.jpg */ Path dst = dstDir.resolve(srcDir.relativize(path)); if (!Files.exists(dst.getParent(), LinkOption.NOFOLLOW_LINKS)) { Files.createDirectories(dst.getParent()); } doResize(path.toFile(), dst.toFile(), width, height, ratio); } return FileVisitResult.CONTINUE; } }); } catch (IOException e) { e.printStackTrace(); } } public static void doResize(File src, File dst, Integer width, Integer height, Double ratio) { try { Builder<File> builder = Thumbnails.of(src); if ((width == null || height == null) && ratio != null) { builder.scale(ratio).toFile(dst); } if ((width != null && height != null) && ratio == null) { builder.size(width, height).toFile(dst); } } catch (IOException e) { System.out.println("Error"); System.out.println("src:" + src.toString()); System.out.println("dst:" + dst.toString()); } } }