[configuration] Use the file system to look for 'lombok.config' files and parse those and cache the results

2 files changed, 203 insertions, 0 deletions

diff --git a/src/core/lombok/core/configuration/ConfigurationErrorReporterFactory.java b/src/core/lombok/core/configuration/ConfigurationErrorReporterFactory.java
new file mode 100644
index 00000000..b5bd9056
--- /dev/null
+++ b/src/core/lombok/core/configuration/ConfigurationErrorReporterFactory.java
@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2014 The Project Lombok Authors.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package lombok.core.configuration;
+
+public interface ConfigurationErrorReporterFactory {
+	ConfigurationErrorReporterFactory CONSOLE = new ConfigurationErrorReporterFactory() {
+		@Override
+		public ConfigurationErrorReporter createFor(final String description) {
+			return new ConfigurationErrorReporter() {
+				@Override
+				public void report(String error) {
+					System.err.printf("Error in %s: %s\n", description, error);
+				}
+			};
+		}
+	};
+	
+	ConfigurationErrorReporter createFor(String description);
+}
diff --git a/src/core/lombok/core/configuration/FileSystemSourceCache.java b/src/core/lombok/core/configuration/FileSystemSourceCache.java
new file mode 100644
index 00000000..50a3bac7
--- /dev/null
+++ b/src/core/lombok/core/configuration/FileSystemSourceCache.java
@@ -0,0 +1,165 @@
+/*
+ * Copyright (C) 2014 The Project Lombok Authors.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package lombok.core.configuration;
+
+import java.io.ByteArrayOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.util.Iterator;
+import java.util.NoSuchElementException;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+import java.util.concurrent.TimeUnit;
+
+public class FileSystemSourceCache {
+	
+	private static String LOMBOK_CONFIG_FILENAME = "lombok.config";
+	private static final long RECHECK_FILESYSTEM = TimeUnit.SECONDS.toMillis(2);
+	private static final long MISSING = -1; 
+	
+	private final ConcurrentMap<File, Content> cache = new ConcurrentHashMap<File, Content>();
+	private final ConfigurationErrorReporterFactory reporterFactory;
+	
+	public FileSystemSourceCache(ConfigurationErrorReporterFactory reporterFactory) {
+		this.reporterFactory = reporterFactory;
+	}
+	
+	public Iterable<ConfigurationSource> sourcesForJavaFile(File javaFile) {
+		final File directory = new File(javaFile.toURI().normalize()).getParentFile();
+		return new Iterable<ConfigurationSource>() {
+			@Override 
+			public Iterator<ConfigurationSource> iterator() {
+				return new Iterator<ConfigurationSource>() {
+					File currentDirectory = directory;
+					ConfigurationSource next;
+					
+					@Override
+					public boolean hasNext() {
+						if (next != null) return true;
+						next = findNext();
+						return next != null;
+					}
+					
+					@Override
+					public ConfigurationSource next() {
+						if (!hasNext()) throw new NoSuchElementException();
+						ConfigurationSource result = next;
+						next = null;
+						return result;
+					}
+					
+					private ConfigurationSource findNext() {
+						while (currentDirectory != null && next == null) {
+							next = getSourceForDirectory(currentDirectory);
+							currentDirectory = currentDirectory.getParentFile();
+						}
+						return next;
+					}
+					
+					@Override
+					public void remove() {
+						throw new UnsupportedOperationException();
+					}
+				};
+			}
+		};
+	}
+	
+	ConfigurationSource getSourceForDirectory(File directory) {
+		if (!directory.exists() && !directory.isDirectory()) throw new IllegalArgumentException("Not a directory: " + directory);
+		long now = System.currentTimeMillis();
+		File configFile = new File(directory, LOMBOK_CONFIG_FILENAME);
+		
+		Content content = ensureContent(directory);
+		synchronized (content) {
+			if (content.lastChecked != MISSING && content.lastChecked - now < RECHECK_FILESYSTEM && getLastModified(configFile) == content.lastModified) {
+				return content.source;
+			}
+			content.lastChecked = now;
+			content.lastModified = getLastModified(configFile);
+			content.source = content.lastModified == MISSING ? null : parse(configFile);
+			return content.source;
+		}
+	}
+	
+	private Content ensureContent(File directory) {
+		Content content = cache.get(directory);
+		if (content != null) {
+			return content;
+		}
+		cache.putIfAbsent(directory, Content.empty());
+		return cache.get(directory);
+	}
+	
+	private ConfigurationSource parse(File configFile) {
+		ConfigurationErrorReporter reporter = reporterFactory.createFor(configFile.getAbsolutePath());
+		try {
+			return StringConfigurationSource.forString(fileToString(configFile), reporter);
+		} catch (Exception e) {
+			reporter.report("Exception while reading file: " + e.getMessage());
+			return null;
+		}
+	}
+	
+	private static final ThreadLocal<byte[]> buffers = new ThreadLocal<byte[]>() {
+		protected byte[] initialValue() {
+			return new byte[65536];
+		}
+	};
+	
+	private String fileToString(File configFile) throws Exception {
+		byte[] b = buffers.get();
+		FileInputStream fis = new FileInputStream(configFile);
+		try {
+			ByteArrayOutputStream out = new ByteArrayOutputStream();
+			while (true) {
+				int r = fis.read(b);
+				if (r == -1) break;
+				out.write(b, 0, r);
+			}
+			return new String(out.toByteArray(), "UTF-8");
+		} finally {
+			fis.close();
+		}
+	}
+	
+	private static final long getLastModified(File file) {
+		if (!file.exists() || !file.isFile()) return MISSING;
+		return file.lastModified();
+	}
+	
+	private static class Content {
+		ConfigurationSource source;
+		long lastModified;
+		long lastChecked;
+		
+		private Content(ConfigurationSource source, long lastModified, long lastChecked) {
+			this.source = source;
+			this.lastModified = lastModified;
+			this.lastChecked = lastChecked;
+		}
+		
+		static Content empty() {
+			return new Content(null, MISSING, MISSING);
+		}
+	}
+}
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