Initial version as posted on github

Initial version by Simeon Andreev (@trancexpress) posted here
eclipse-jdt/eclipse.jdt#54 (comment)

src/test/EclipseWikiCrawler.java

@@ -0,0 +1,162 @@
+package test;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.net.URL;
+import java.nio.channels.Channels;
+import java.nio.channels.ReadableByteChannel;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.LinkedHashMap;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+public class EclipseWikiCrawler {
+
+    private static final String NO_TITLE = "no_title";
+    private static final Pattern TITLE_PATTERN = Pattern.compile(".*<title>(.*)</title>.*");
+    private static final Pattern IMAGE_PATTERN = Pattern.compile(".*\\[\\[Image:([^\\]]*)\\]\\].*");
+
+    public static void main(String[] args) throws IOException {
+    	Map<String, List<String> > images = getImages();
+        String site = "https://wiki.eclipse.org/File:";
+        for (Entry<String, List<String>> entry : images.entrySet()) {
+        	String title = entry.getKey();
+        	String path = title.replace(' ', '_');
+        	int indexOfLastSlash = path.lastIndexOf('/');
+        	if (indexOfLastSlash == -1) {
+        		path = "";
+        	} else {
+        		path = path.substring(0, indexOfLastSlash);
+        	}
+        	Set<String> imageNames = new LinkedHashSet<>(entry.getValue());
+        	for (String imageName : imageNames) {
+        		URL url = new URL(site + imageName);
+        		try (BufferedReader in = new BufferedReader(new InputStreamReader(url.openStream()))) {
+        			String inputLine;
+        			while ((inputLine = in.readLine()) != null) {
+        				int srcStartIndex = inputLine.indexOf("src=\"/images/");
+        				if (srcStartIndex != -1) {
+        					int srcEndIndex = inputLine.indexOf(imageName, srcStartIndex);
+        					if (srcEndIndex != -1) {
+        						String srcPart = inputLine.substring(srcStartIndex, srcEndIndex);
+        						String src = srcPart.substring("src=\"".length());
+        						String imageUrl = "https://wiki.eclipse.org/" + src + imageName;
+        						downloadImage(imageUrl, "/data/git/eclipse/eclipse.jdt/wiki/" + path +"/" + imageName);
+        						break;
+        					}
+        				}
+        			}
+        		}
+        	}
+        }
+    }
+
+    private static Map<String, List<String> > getImages() throws IOException {
+    	Map<String, List<String> > images = new LinkedHashMap<>();
+    	String xmlFile = "/tmp/wikiexport/Eclipsepedia-20230215110023.xml";
+    	List<String> lines = Files.readAllLines(Paths.get(xmlFile));
+    	String currentTitle = NO_TITLE;
+    	for (String line : lines) {
+    		Matcher m = TITLE_PATTERN.matcher(line);
+    		if (m.matches()) {
+    			currentTitle = m.group(1);
+    			continue;
+    		}
+    		m = IMAGE_PATTERN.matcher(line);
+    		if (m.matches()) {
+    			String image = m.group(1);
+    			List<String> list = images.get(currentTitle);
+    			if (list == null) {
+    				list = new ArrayList<>();
+    				images.put(currentTitle, list);
+    			}
+				list.add(image);
+    		}
+    	}
+    	return images;
+    }
+
+    private static void downloadImage(String url, String fileLocation) {
+        Address address = new Address(url);
+        Image image = new Image(address, fileLocation);
+        try {
+            image.download();
+            if (!image.successful()) {
+            	throw new IOException("Failed to download image: " + url);
+            }
+            System.out.println("Done with " + address.url() + " -> " + fileLocation);
+        } catch (IOException e) {
+            System.err.println("Error when downloading " + address.url() + " : " + e.getMessage());
+        }
+    }
+
+    private static class Address {
+
+        private final String url;
+
+        public Address(String url) {
+            this.url = url;
+        }
+
+        public String url() {
+            return url;
+        }
+    }
+
+    private static class Image {
+
+        private static final int MIN_BYTES = 1;
+
+        private final Address address;
+        private final String location;
+
+        private boolean successful;
+
+
+        public Image(Address address, String location) {
+            this.address = address;
+            this.location = location;
+            successful = false;
+        }
+
+
+        public void download() throws IOException {
+            successful = true;
+
+            File imageOnDisk = new File(location);
+            if (imageOnDisk.exists()) {
+                return;
+            }
+
+            URL website = new URL(address.url());
+            try (
+                ReadableByteChannel rbc = Channels.newChannel(website.openStream());
+                FileOutputStream fos = new FileOutputStream(imageOnDisk)) {
+
+                fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
+            }
+
+
+            if (imageOnDisk.exists() && (imageOnDisk.length() < MIN_BYTES)) {
+                imageOnDisk.delete();
+                successful = false;
+            }
+        }
+
+        public boolean successful() {
+            return successful;
+        }
+    }
+
+}