Use slf4j

Signed-off-by: Minecon724 <git@m724.eu>

src/main/java/eu/m724/blog/BlogBuilder.java

@@ -10,6 +10,8 @@ import org.apache.commons.compress.compressors.CompressorException;
 import org.apache.commons.io.file.PathUtils;
 import org.eclipse.jgit.api.Git;
 import org.eclipse.jgit.lib.RepositoryBuilder;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
 import java.nio.file.FileAlreadyExistsException;
@@ -27,6 +29,8 @@ import java.util.stream.Collectors;
  * source for the blog's content and configuration.
  */
 public class BlogBuilder {
+    private static final Logger LOGGER = LoggerFactory.getLogger(BlogBuilder.class);
+
     private final Git git;
     private final Path workingDirectory;
 
@@ -121,7 +125,7 @@ public class BlogBuilder {
      * @throws IOException if an I/O error occurs
      */
     public void build() throws IOException {
-        System.out.println("Loading site...");
+        LOGGER.debug("Loading site...");
         if (site == null)
             this.site = Site.fromConfig(workingDirectory.resolve("site.yml"));
 
@@ -131,21 +135,21 @@ public class BlogBuilder {
         if (template == null)
             this.template = new TemplateRenderer(templateDirectory);
 
-        System.out.println("Copying assets...");
+        LOGGER.debug("Copying assets...");
         copyTree(workingDirectory.resolve("assets"), outputDirectory.resolve("assets"));
         copyTree(templateDirectory.resolve("static"), outputDirectory.resolve("static"));
 
-        System.out.println("Rendering posts...");
+        LOGGER.debug("Rendering posts...");
         var posts = renderPosts();
 
-        System.out.println("Rendering meta...");
+        LOGGER.debug("Rendering meta...");
         posts.sort(Comparator.comparing(Post::createdAt).reversed());
         Files.writeString(outputDirectory.resolve("index.html"), template.renderIndex(site, posts));
 
         Files.writeString(outputDirectory.resolve("posts.rss"), Feed.generateRss(site, posts));
 
         if (!renderOptions.compress().isEmpty()) {
-            System.out.println("Compressing...");
+            LOGGER.debug("Compressing...");
             compressOutput();
         }
     }
@@ -162,7 +166,7 @@ public class BlogBuilder {
                     continue; // directory is created below
 
                 if (!path.toString().endsWith(".html")) {
-                    System.out.println("Post " + path.getFileName() + ": unsupported file type");
+                    LOGGER.warn("Post {}: unsupported file type", path.getFileName());
                     continue;
                 }
 
@@ -170,7 +174,7 @@ public class BlogBuilder {
                 var post = Post.fromFile(git, path);
 
                 if (post.draft() && !renderDrafts) {
-                    System.out.println("Post " + path.getFileName() + ": draft, ignoring");
+                    LOGGER.info("Post {}: draft, ignoring", path.getFileName());
                     continue;
                 }
 
@@ -204,7 +208,7 @@ public class BlogBuilder {
                 try {
                     compressor.compress(path);
                 } catch (CompressorException e) {
-                    System.err.printf("Exception compressing %s to %s: %s%n", path, compressor.getAlgorithm(), e.getMessage());
+                    LOGGER.error("Error compressing {} to {}: {}", path, compressor.getAlgorithm(), e.getMessage());
                 }
             }
         }

src/main/java/eu/m724/blog/Main.java

@@ -1,14 +1,16 @@
 package eu.m724.blog;
 
 import org.apache.commons.cli.*;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
 import java.nio.file.Path;
 
 public class Main {
-    public static void main(String[] args) throws IOException {
-        System.out.println("Hello world!");
+    private static final Logger LOGGER = LoggerFactory.getLogger(Main.class);
 
+    public static void main(String[] args) throws IOException {
         var commandLine = getCommandLine(args);
 
         if (commandLine == null)
@@ -37,12 +39,12 @@ public class Main {
 
         builder.mkdirs(force);
 
-        System.out.println("---- START BUILD ----");
+        LOGGER.info("Building...");
         builder.build();
-        System.out.println("----- END BUILD -----");
 
         var end = System.nanoTime();
-        System.out.printf("Exported to %s (%.2f ms)\n", outputDirectory, (end - start) / 1000000.0);
+        //                                                                            BAD
+        LOGGER.info("Exported to {} in {} ms", outputDirectory.toAbsolutePath(), "%.2f".formatted((end - start) / 1000000.0));
 
         /* Server process */
 

src/main/java/eu/m724/blog/Server.java

@@ -2,6 +2,8 @@ package eu.m724.blog;
 
 import com.sun.net.httpserver.HttpServer;
 import com.sun.net.httpserver.SimpleFileServer;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
 import java.net.InetSocketAddress;
@@ -13,6 +15,8 @@ import java.nio.file.Path;
  * {@link SimpleFileServer} is used.
  */
 public class Server {
+    private static final Logger LOGGER = LoggerFactory.getLogger(Server.class);
+
     private final Path webroot;
     private InetSocketAddress listenAddress;
 
@@ -48,7 +52,7 @@ public class Server {
         server.createContext("/", SimpleFileServer.createFileHandler(webroot.toAbsolutePath()));
         server.start();
 
-        System.out.println("Server started on http:/" + server.getAddress());
+        LOGGER.info("Server started on http:/{}", server.getAddress());
 
         this.listenAddress = server.getAddress();
     }
@@ -63,9 +67,10 @@ public class Server {
             if (code != 0) {
                 throw new Exception("Exit code " + code);
             }
-            System.out.println("Opened browser");
+
+            LOGGER.info("Opened browser"); // TODO make this debug?
         } catch (Exception e) {
-            System.out.println("Failed to open browser: " + e);
+            LOGGER.error("Failed to open browser: {}", String.valueOf(e));
         }
     }
 }

src/main/java/eu/m724/blog/data/Post.java

@@ -2,6 +2,8 @@ package eu.m724.blog.data;
 
 import org.eclipse.jgit.api.Git;
 import org.eclipse.jgit.api.errors.GitAPIException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.*;
 import java.nio.file.Files;
@@ -40,6 +42,8 @@ public record Post(
         Map<String, String> custom,
         String rawContent
 ) {
+    private static final Logger LOGGER = LoggerFactory.getLogger(Post.class);
+
     /**
      * Creates a {@link Post} instance by reading and parsing the content of a post file.
      * <p>
@@ -71,7 +75,7 @@ public record Post(
                 break;
 
             if (properties.putIfAbsent(key, data) != null)
-                System.out.printf("Post %s: Duplicate property \"%s\". Only the first one will be used.\n", slug, key);
+                LOGGER.warn("[Post {}] Ignoring duplicate property: {}", slug, key);
         }
 
         var content = String.join("\n", lines).strip();
@@ -122,7 +126,7 @@ public record Post(
             }
         } catch (GitAPIException e) {
             draft = true;
-            System.out.printf("%s: Git exception, making draft: %s\n", slug, e.getMessage());
+            LOGGER.warn("[Post {}] Draft because of a Git exception: {}\n", slug, e.getMessage());
         }
 
         return new Post(slug, title, summary, draft, revisions, createdBy, createdAt, modifiedBy, modifiedAt, custom, content);

src/main/java/eu/m724/blog/data/RenderOptions.java

@@ -1,5 +1,7 @@
 package eu.m724.blog.data;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.snakeyaml.engine.v2.api.Load;
 import org.snakeyaml.engine.v2.api.LoadSettings;
 
@@ -13,6 +15,8 @@ import java.util.Map;
 public record RenderOptions(
         List<String> compress // TODO rename?
 ) {
+    private static final Logger LOGGER = LoggerFactory.getLogger(RenderOptions.class);
+
     /**
      * Creates a {@link Site} object by reading and parsing the configuration file at the specified path.<br>
      * The configuration file must be a JSON file.
@@ -31,12 +35,11 @@ public record RenderOptions(
             var value = yaml.get(key);
 
             switch (key) {
-                case "compress": {
+                case "compress":
                     compress = (List<String>) value;
-                }
-                default: {
-                    System.out.println("Unrecognized option (render): " + key);
-                }
+                    break;
+                default:
+                    LOGGER.warn("Ignoring unrecognized render option: {}", key);
             }
         }
 

src/main/resources/simplelogger.properties

@@ -0,0 +1,11 @@
+org.slf4j.simpleLogger.defaultLogLevel=info
+
+# TODO maybe?
+#org.slf4j.simpleLogger.showDateTime=true
+#org.slf4j.simpleLogger.dateTimeFormat=HH:mm:ss.SSS
+
+org.slf4j.simpleLogger.showThreadName=false
+org.slf4j.simpleLogger.showShortLogName=true
+org.slf4j.simpleLogger.levelInBrackets=true
+
+org.slf4j.simpleLogger.logFile=System.out