scijava · dscho · Oct 15, 2014 · Oct 11, 2014 · Jun 27, 2014 · Jul 1, 2014
diff --git a/src/main/java/org/scijava/prefs/DefaultPrefService.java b/src/main/java/org/scijava/prefs/DefaultPrefService.java
@@ -378,6 +378,28 @@ public List<String> getList(final Class<?> prefClass) {
 		return getList(preferences);
 	}
 
+	@Override
+	public Iterable<String> getIterable(final String key) {
+		return getIterable((Class<?>) null, key);
+	}
+
+	@Override
+	public Iterable<String> getIterable(final Class<?> prefClass, final String key) {
+		final Preferences preferences = prefs(prefClass);
+		return getIterable(preferences.node(key));
+	}
+
+	@Override
+	public void putIterable(final Iterable<String> iterable, final String key) {
+		putIterable((Class<?>) null, iterable, key);
+	}
+
+	@Override
+	public void putIterable(final Class<?> prefClass, final Iterable<String> iterable, final String key) {
+		final Preferences preferences = prefs(prefClass);
+		putIterable(preferences.node(key), iterable);
+	}
+
 	// -- Helper methods --
 
 	private void clear(final Preferences preferences, final String key) {
@@ -460,6 +482,60 @@ private List<String> getList(final Preferences preferences) {
 		return list;
 	}
 
+	private void putIterable(final Preferences preferences,
+		final Iterable<String> iterable)
+	{
+		if (preferences == null) {
+			throw new IllegalArgumentException("Preferences not set.");
+		}
+		int index = 0;
+		for (final String value : iterable) {
+			preferences.put("" + index++, value == null ? null : value.toString());
+		}
+	}
+
+	private Iterable<String> getIterable(final Preferences preferences)
+	{
+		if (preferences == null) {
+			throw new IllegalArgumentException("Preferences not set.");
+		}
+		return new Iterable<String>() {
+			@Override
+			public Iterator<String> iterator() {
+				return new Iterator<String>() {
+					private String value;
+					private int index;
+					{
+						findNext();
+					}
+
+					@Override
+					public String next() {
+						final String result = value;
+						findNext();
+						return result;
+					}
+
+					@Override
+					public boolean hasNext() {
+						return value != null;
+					}
+
+					@Override
+					public void remove() {
+						throw new UnsupportedOperationException();
+					}
+
+					private void findNext() {
+						if (index < 0) return;
+						value = preferences.get("" + index, null);
+						index = value == null ? -1 : index + 1;
+					}
+				};
+			}
+		};
+	}
+
 	private Preferences prefs(final Class<?> c) {
 		return Preferences.userNodeForPackage(c == null ? PrefService.class : c);
 	}

diff --git a/src/main/java/org/scijava/prefs/PrefService.java b/src/main/java/org/scijava/prefs/PrefService.java
@@ -194,4 +194,24 @@ public interface PrefService extends SciJavaService {
 	 * prefs.
 	 */
 	List<String> getList(Class<?> prefClass);
+
+	/**
+	 * Puts an iterable into the preferences.
+	 */
+	void putIterable(Iterable<String> iterable, String key);
+
+	/**
+	 * Puts an iterable into the preferences.
+	 */
+	void putIterable(Class<?> prefClass, Iterable<String> iterable, String key);
+
+	/**
+	 * Gets an iterable from the preferences.
+	 */
+	Iterable<String> getIterable(String key);
+
+	/**
+	 * Gets an iterable from the preferences.
+	 */
+	Iterable<String> getIterable(Class<?> prefClass, String key);
 }
diff --git a/src/main/java/org/scijava/script/DefaultScriptInterpreter.java b/src/main/java/org/scijava/script/DefaultScriptInterpreter.java
@@ -0,0 +1,102 @@
+/*
+ * #%L
+ * SciJava Common shared library for SciJava software.
+ * %%
+ * Copyright (C) 2009 - 2014 Board of Regents of the University of
+ * Wisconsin-Madison, Broad Institute of MIT and Harvard, and Max Planck
+ * Institute of Molecular Cell Biology and Genetics.
+ * %%
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * 
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ * #L%
+ */
+package org.scijava.script;
+
+import javax.script.ScriptEngine;
+import javax.script.ScriptException;
+
+import org.scijava.prefs.PrefService;
+
+/**
+ * The default implementation of a {@link ScriptInterpreter}.
+ *  
+ * @author Johannes Schindelin
+ */
+public class DefaultScriptInterpreter implements ScriptInterpreter {
+
+	private final ScriptLanguage language;
+	private final ScriptEngine engine;
+	private final History history;
+
+	/**
+	 * Constructs a new {@link DefaultScriptInterpreter}.
+	 * 
+	 * @param scriptService the script service
+	 * @param language the script language
+	 */
+	public DefaultScriptInterpreter(final PrefService prefs,
+		final ScriptService scriptService, final ScriptLanguage language)
+	{
+		this.language = language;
+		engine = language.getScriptEngine();
+		history = new History(prefs, engine.getClass().getName());
+		readHistory();
+	}
+
+	@Override
+	public synchronized void readHistory() {
+		if (history == null) return;
+		history.read();
+	}
+
+	@Override
+	public synchronized void writeHistory() {
+		if (history == null) return;
+		history.write();
+	}
+
+	@Override
+	public synchronized String walkHistory(final String currentCommand,
+		final boolean forward)
+	{
+		if (history == null) return currentCommand;
+		history.replace(currentCommand);
+		return forward ? history.next() : history.previous();
+	}
+
+	@Override
+	public void eval(final String command) throws ScriptException {
+		if (history != null) history.add(command);
+		if (engine == null) throw new java.lang.IllegalArgumentException();
+		engine.eval(command);
+	}
+
+	@Override
+	public ScriptLanguage getLanguage() {
+		return language;
+	}
+
+	@Override
+	public ScriptEngine getEngine() {
+		return engine;
+	}
+
+}
diff --git a/src/main/java/org/scijava/script/History.java b/src/main/java/org/scijava/script/History.java
@@ -0,0 +1,145 @@
+/*
+ * #%L
+ * SciJava Common shared library for SciJava software.
+ * %%
+ * Copyright (C) 2009 - 2014 Board of Regents of the University of
+ * Wisconsin-Madison, Broad Institute of MIT and Harvard, and Max Planck
+ * Institute of Molecular Cell Biology and Genetics.
+ * %%
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * 
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ * #L%
+ */
+
+package org.scijava.script;
+
+import org.scijava.prefs.PrefService;
+import org.scijava.util.LastRecentlyUsed;
+
+/**
+ * Container for a script language's interpreter history.
+ * 
+ * @author Johannes Schindelin
+ */
+class History {
+
+	protected static final long serialVersionUID = 1L;
+
+	private static final String PREFIX = "History.";
+	private final int MAX_ENTRIES = 1000;
+
+	private final PrefService prefs;
+	private final String name;
+	private final LastRecentlyUsed<String> entries = new LastRecentlyUsed<String>(MAX_ENTRIES);
+	private String currentCommand = "";
+	private int position = -1;
+
+	/**
+	 * Constructs a history object for a given scripting language.
+	 * 
+	 * @param name the name of the scripting language
+	 */
+	public History(final PrefService prefs, final String name) {
+		this.prefs = prefs;
+		this.name = name;
+	}
+
+	/**
+	 * Read back a persisted history.
+	 */
+	public void read() {
+		entries.clear();
+		for (final String item : prefs.getIterable(getClass(), PREFIX + name)) {
+			entries.addToEnd(item);
+		};
+	}
+
+	/**
+	 * Persist the history.
+	 * 
+	 * @see {@link Prefs}
+	 */
+	public void write() {
+		prefs.putIterable(getClass(), entries, PREFIX + name);
+	}
+
+	/**
+	 * Adds the most recently issued command.
+	 * 
+	 * @param command the most recent command to add to the history
+	 */
+	public void add(final String command) {
+		entries.add(command);
+		position = -1;
+		currentCommand = "";
+	}
+
+	public boolean replace(final String currentCommand) {
+		if (position < 0) {
+			this.currentCommand = currentCommand;
+			return false;
+		}
+		return entries.replace(position, currentCommand);
+	}
+
+	/**
+	 * Navigates to the next (more recent) command.
+	 * <p>
+	 * This method wraps around, i.e. it returns {@code null} when there is no
+	 * more-recent command in the history.
+	 * </p>
+	 * 
+	 * @return the next command
+	 */
+	public String next() {
+		position = entries.next(position);
+		return position < 0 ? currentCommand : entries.get(position);
+	}
+
+	/**
+	 * Navigates to the previous (i.e less recent) command.
+	 * <p>
+	 * This method wraps around, i.e. it returns {@code null} when there is no
+	 * less-recent command in the history.
+	 * </p>
+	 * 
+	 * @return the previous command
+	 */
+	public String previous() {
+		position = entries.previous(position);
+		return position < 0 ? currentCommand : entries.get(position);
+	}
+
+	@Override
+	public String toString() {
+		final StringBuilder builder = new StringBuilder();
+		int position = -1;
+		for (;;) {
+			position = entries.previous(position);
+			if (position < 0) break;
+			if (builder.length() > 0) builder.append(" -> ");
+			if (this.position == position) builder.append("[");
+			builder.append(entries.get(position));
+			if (this.position == position) builder.append("]");
+		}
+		return builder.toString();
+	}
+}