* added FunctionIterator

* added Preferences Wrapper (Map, List)

source/net/sourceforge/tuned/ExceptionUtil.java

@@ -0,0 +1,24 @@
+
+package net.sourceforge.tuned;
+
+
+public class ExceptionUtil {
+	
+	public static Throwable getRootCause(Throwable t) {
+		while (t.getCause() != null) {
+			t = t.getCause();
+		}
+		
+		return t;
+	}
+	
+
+	public static RuntimeException asRuntimeException(Throwable t) {
+		if (t instanceof RuntimeException) {
+			return (RuntimeException) t;
+		}
+		
+		return new RuntimeException(t);
+	}
+	
+}

source/net/sourceforge/tuned/FunctionIterator.java

@@ -0,0 +1,101 @@
+
+package net.sourceforge.tuned;
+
+
+import java.util.Iterator;
+import java.util.NoSuchElementException;
+
+
+public class FunctionIterator<S, T> implements Iterator<T> {
+	
+	/**
+	 * A Function transforms one Object into another.
+	 * 
+	 * @param <S> type of source Objects
+	 * @param <T> type Objects are transformed into
+	 */
+	public static interface Function<S, T> {
+		
+		/**
+		 * Transform the given sourceValue into any kind of Object.
+		 * 
+		 * @param sourceValue - the Object to transform
+		 * @return the transformed version of the object
+		 */
+		public T evaluate(S sourceValue);
+	}
+	
+	private final Iterator<S> sourceIterator;
+	private final Function<S, T> function;
+	
+	
+	public FunctionIterator(Iterable<S> source, Function<S, T> function) {
+		this(source.iterator(), function);
+	}
+	
+
+	public FunctionIterator(Iterator<S> iterator, Function<S, T> function) {
+		this.sourceIterator = iterator;
+		this.function = function;
+	}
+	
+
+	@Override
+	public boolean hasNext() {
+		try {
+			return peekNext() != null;
+		} catch (Exception e) {
+			return true;
+		}
+	}
+	
+
+	@Override
+	public T next() {
+		if (!hasNext())
+			throw new NoSuchElementException();
+		
+		try {
+			return peekNext();
+		} finally {
+			cache = null;
+			currentException = null;
+		}
+	}
+	
+	private T cache = null;
+	private RuntimeException currentException = null;
+	
+	
+	private T peekNext() {
+		while (cache == null && (sourceIterator.hasNext() || currentException != null)) {
+			if (currentException != null)
+				throw currentException;
+			
+			try {
+				cache = transform(sourceIterator.next());
+			} catch (RuntimeException e) {
+				currentException = e;
+			}
+		}
+		
+		return cache;
+	}
+	
+
+	private T transform(S sourceValue) {
+		return function.evaluate(sourceValue);
+	}
+	
+
+	/**
+	 * The remove operation is not supported by this implementation of <code>Iterator</code>.
+	 * 
+	 * @throws UnsupportedOperationException if this method is invoked.
+	 * @see java.util.Iterator
+	 */
+	@Override
+	public void remove() {
+		throw new UnsupportedOperationException();
+	}
+}

source/net/sourceforge/tuned/PreferencesList.java

@@ -0,0 +1,96 @@
+
+package net.sourceforge.tuned;
+
+
+import java.util.AbstractList;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.prefs.Preferences;
+
+import net.sourceforge.tuned.PreferencesMap.Adapter;
+
+
+public class PreferencesList<T> extends AbstractList<T> {
+	
+	private final PreferencesMap<T> prefs;
+	
+	
+	public PreferencesList(PreferencesMap<T> preferencesMap) {
+		this.prefs = preferencesMap;
+	}
+	
+
+	@Override
+	public T get(int index) {
+		return prefs.get(key(index));
+	}
+	
+
+	private String key(int index) {
+		return Integer.toString(index);
+	}
+	
+
+	@Override
+	public int size() {
+		return prefs.size();
+	}
+	
+
+	@Override
+	public boolean add(T e) {
+		prefs.put(key(size()), e);
+		return true;
+	}
+	
+
+	@Override
+	public T remove(int index) {
+		
+		int lastIndex = size() - 1;
+		
+		List<T> shiftList = new ArrayList<T>(subList(index, lastIndex + 1));
+		
+		T value = shiftList.remove(0);
+		
+		prefs.remove(key(lastIndex));
+		
+		for (T element : shiftList) {
+			set(index, element);
+			index++;
+		}
+		
+		return value;
+	}
+	
+
+	@Override
+	public T set(int index, T element) {
+		if (index < 0 || index >= size())
+			throw new IndexOutOfBoundsException();
+		
+		return prefs.put(key(index), element);
+	}
+	
+
+	@Override
+	public void clear() {
+		prefs.clear();
+	}
+	
+
+	public void set(List<T> data) {
+		clear();
+		addAll(data);
+	}
+	
+
+	public static <T> PreferencesList<T> map(Preferences prefs, Class<T> type) {
+		return new PreferencesList<T>(PreferencesMap.map(prefs, type));
+	}
+	
+
+	public static <T> PreferencesList<T> map(Preferences prefs, Adapter<T> adapter) {
+		return new PreferencesList<T>(PreferencesMap.map(prefs, adapter));
+	}
+}

source/net/sourceforge/tuned/PreferencesMap.java

@@ -0,0 +1,316 @@
+
+package net.sourceforge.tuned;
+
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.Serializable;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.prefs.BackingStoreException;
+import java.util.prefs.Preferences;
+
+
+public class PreferencesMap<T> implements Map<String, T> {
+	
+	private final Preferences prefs;
+	private final Adapter<T> adapter;
+	
+	
+	public PreferencesMap(Preferences prefs, Adapter<T> adapter) {
+		this.prefs = prefs;
+		this.adapter = adapter;
+	}
+	
+
+	@Override
+	public T get(Object key) {
+		if (key instanceof String) {
+			return adapter.get(prefs, (String) key);
+		}
+		
+		throw new IllegalArgumentException("Key must be a String");
+	}
+	
+
+	@Override
+	public T put(String key, T value) {
+		adapter.put(prefs, key, value);
+		
+		return value;
+	}
+	
+
+	/**
+	 * @return always null
+	 */
+	@Override
+	public T remove(Object key) {
+		if (key instanceof String) {
+			prefs.remove((String) key);
+		}
+		
+		return null;
+	}
+	
+
+	public String[] keys() {
+		try {
+			return prefs.keys();
+		} catch (BackingStoreException e) {
+			throw new RuntimeException(e);
+		}
+	}
+	
+
+	@Override
+	public void clear() {
+		try {
+			prefs.clear();
+		} catch (BackingStoreException e) {
+			throw new RuntimeException(e);
+		}
+	}
+	
+
+	public void set(Map<String, T> data) {
+		clear();
+		putAll(data);
+	}
+	
+
+	@Override
+	public boolean containsKey(Object key) {
+		if (key instanceof String) {
+			return Arrays.asList(keys()).contains(key);
+		}
+		
+		return false;
+	}
+	
+
+	@Override
+	public boolean containsValue(Object value) {
+		for (String key : keys()) {
+			if (value.equals(get(key)))
+				return true;
+		}
+		
+		return false;
+	}
+	
+
+	@Override
+	public Set<Map.Entry<String, T>> entrySet() {
+		Set<Map.Entry<String, T>> entries = new LinkedHashSet<Map.Entry<String, T>>();
+		
+		for (String key : keys()) {
+			entries.add(new Entry(key));
+		}
+		
+		return entries;
+	}
+	
+
+	@Override
+	public boolean isEmpty() {
+		return size() == 0;
+	}
+	
+
+	@Override
+	public Set<String> keySet() {
+		return new HashSet<String>(Arrays.asList(keys()));
+	}
+	
+
+	@Override
+	public void putAll(Map<? extends String, ? extends T> map) {
+		for (String key : map.keySet()) {
+			put(key, map.get(key));
+		}
+	}
+	
+
+	@Override
+	public int size() {
+		return keys().length;
+	}
+	
+
+	@Override
+	public Collection<T> values() {
+		List<T> values = new ArrayList<T>();
+		
+		for (String key : keys()) {
+			values.add(get(key));
+		}
+		
+		return values;
+	}
+	
+	
+	private class Entry implements Map.Entry<String, T> {
+		
+		private final String key;
+		
+		
+		public Entry(String key) {
+			this.key = key;
+		}
+		
+
+		@Override
+		public String getKey() {
+			return key;
+		}
+		
+
+		@Override
+		public T getValue() {
+			return get(key);
+		}
+		
+
+		@Override
+		public T setValue(T value) {
+			return put(key, value);
+		}
+		
+	}
+	
+	
+	@SuppressWarnings("unchecked")
+	public static <T> PreferencesMap<T> map(Preferences prefs, Class<T> type) {
+		Adapter<T> adapter;
+		
+		if (type == String.class) {
+			// prefer StringAdapter, because SimpleAdapter would use the copy constructor of String, instead of returning the values directly
+			adapter = (Adapter<T>) new StringAdapter();
+		} else {
+			adapter = new SimpleAdapter(type);
+		}
+		
+		return map(prefs, adapter);
+	}
+	
+
+	public static <T> PreferencesMap<T> map(Preferences prefs, Adapter<T> adapter) {
+		return new PreferencesMap<T>(prefs, adapter);
+	}
+	
+	
+	public static interface Adapter<T> {
+		
+		public T get(Preferences prefs, String key);
+		
+
+		public void put(Preferences prefs, String key, T value);
+	}
+	
+
+	public static class StringAdapter implements Adapter<String> {
+		
+		@Override
+		public String get(Preferences prefs, String key) {
+			return prefs.get(key, null);
+		}
+		
+
+		@Override
+		public void put(Preferences prefs, String key, String value) {
+			prefs.put(key, value);
+		}
+		
+	}
+	
+
+	public static class SimpleAdapter<T> implements Adapter<T> {
+		
+		private final Constructor<T> constructor;
+		
+		
+		public SimpleAdapter(Class<T> type) {
+			try {
+				constructor = type.getConstructor(String.class);
+			} catch (Exception e) {
+				throw new IllegalArgumentException(e);
+			}
+		}
+		
+
+		@Override
+		public T get(Preferences prefs, String key) {
+			String stringValue = prefs.get(key, null);
+			
+			if (stringValue == null)
+				return null;
+			
+			try {
+				return constructor.newInstance(stringValue);
+			} catch (InvocationTargetException e) {
+				throw ExceptionUtil.asRuntimeException(e.getCause());
+			} catch (Exception e) {
+				throw new RuntimeException(e);
+			}
+		}
+		
+
+		@Override
+		public void put(Preferences prefs, String key, T value) {
+			prefs.put(key, value.toString());
+		}
+		
+	}
+	
+
+	public static class SerializableAdapter<T extends Serializable> implements Adapter<T> {
+		
+		@SuppressWarnings("unchecked")
+		@Override
+		public T get(Preferences prefs, String key) {
+			byte[] bytes = prefs.getByteArray(key, null);
+			
+			if (bytes == null)
+				return null;
+			
+			try {
+				ObjectInputStream in = new ObjectInputStream(new ByteArrayInputStream(bytes));
+				Object object = in.readObject();
+				in.close();
+				
+				return (T) object;
+			} catch (Exception e) {
+				throw new RuntimeException(e);
+			}
+		}
+		
+
+		@Override
+		public void put(Preferences prefs, String key, T value) {
+			ByteArrayOutputStream buffer = new ByteArrayOutputStream();
+			
+			try {
+				ObjectOutputStream out = new ObjectOutputStream(buffer);
+				out.writeObject(value);
+				out.close();
+				
+				prefs.putByteArray(key, buffer.toByteArray());
+			} catch (IOException e) {
+				throw new RuntimeException(e);
+			}
+		}
+	}
+	
+}