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diff --git a/src/main/java/net/pterodactylus/sonitus/data/filter/PredicateFilter.java b/src/main/java/net/pterodactylus/sonitus/data/filter/PredicateFilter.java
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index 0000000..1e8c7fa
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+++ b/src/main/java/net/pterodactylus/sonitus/data/filter/PredicateFilter.java
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+/*
+ * Sonitus - PredicateFilter.java - Copyright © 2013 David Roden
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package net.pterodactylus.sonitus.data.filter;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+import java.io.IOException;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+import net.pterodactylus.sonitus.data.Filter;
+import net.pterodactylus.sonitus.data.Metadata;
+
+import com.google.common.base.Predicate;
+
+/**
+ * {@link Filter} implementation that uses a {@link Predicate} to determine
+ * whether a filter will be used or the data will only be passed through.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+public class PredicateFilter extends DummyFilter {
+
+	/** The predicate. */
+	private final Predicate<Metadata> metadataPredicate;
+
+	/** The filter to use if the predicate matches. */
+	private final Filter filter;
+
+	/** Whether the predicate currently matches. */
+	private final AtomicBoolean metadataMatches = new AtomicBoolean(false);
+
+	/**
+	 * Creates a new predicate filter.
+	 *
+	 * @param metadataPredicate
+	 * 		The predicate to evaluate every time the metadata changes
+	 * @param filter
+	 * 		The filter to use if the predicate matches the metadata
+	 */
+	public PredicateFilter(Predicate<Metadata> metadataPredicate, Filter filter) {
+		this.metadataPredicate = metadataPredicate;
+		this.filter = filter;
+	}
+
+	//
+	// FILTER METHODS
+	//
+
+	@Override
+	public void open(Metadata metadata) throws IOException {
+		checkNotNull(metadata, "metadata must not be null");
+
+		metadataMatches.set(metadataPredicate.apply(metadata));
+		if (metadataMatches.get()) {
+			filter.open(metadata);
+		} else {
+			super.open(metadata);
+		}
+	}
+
+	@Override
+	public void close() {
+		if (metadataMatches.get()) {
+			filter.close();
+		} else {
+			super.close();
+		}
+	}
+
+	@Override
+	public void metadataUpdated(Metadata metadata) {
+		metadataMatches.set(metadataPredicate.apply(metadata));
+		if (metadataMatches.get()) {
+			filter.metadataUpdated(metadata);
+		} else {
+			super.metadataUpdated(metadata);
+		}
+	}
+
+	@Override
+	public void process(byte[] buffer) throws IOException {
+		if (metadataMatches.get()) {
+			filter.process(buffer);
+		} else {
+			super.process(buffer);
+		}
+	}
+
+	@Override
+	public Metadata metadata() {
+		if (metadataMatches.get()) {
+			return filter.metadata();
+		} else {
+			return super.metadata();
+		}
+	}
+
+	@Override
+	public byte[] get(int bufferSize) throws IOException {
+		if (metadataMatches.get()) {
+			return filter.get(bufferSize);
+		} else {
+			return super.get(bufferSize);
+		}
+	}
+
+}