org.fife.ui.rtextarea.ClipboardHistory Maven / Gradle / Ivy
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/*
* 08/29/2014
*
* ClipboardHistory.java - A history of text added to the clipboard.
*
* This library is distributed under a modified BSD license. See the included
* LICENSE file for details.
*/
package org.fife.ui.rtextarea;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
/**
* Listens for cuts and copies from instances of {@link RTextArea}. This is
* used for the "clipboard history" shortcut (Ctrl+Shift+V by default).
*
* Note that this class does not listen for all events on the system clipboard,
* because that functionality is pretty fragile. See
*
* https://stackoverflow.com/questions/5484927/listen-to-clipboard-changes-check-ownership
* for more information.
*
* @author Robert Futrell
* @version 1.0
*/
public final class ClipboardHistory {
private static ClipboardHistory instance;
private List history;
private int maxSize;
private static final int DEFAULT_MAX_SIZE = 12;
private ClipboardHistory() {
history = new ArrayList<>();
maxSize = DEFAULT_MAX_SIZE;
}
/**
* Adds an entry to the clipboard history.
*
* @param str The text to add.
* @see #getHistory()
*/
public void add(String str) {
int size = history.size();
if (size==0) {
history.add(str);
}
else {
int index = history.indexOf(str);
if (index!=size-1) {
if (index>-1) {
history.remove(index);
}
history.add(str);
}
trim();
}
}
/**
* Returns the singleton instance of this class, lazily creating it if
* necessary.
*
* This method should only be called on the EDT.
*
* @return The singleton instance of this class.
*/
public static ClipboardHistory get() {
if (instance==null) {
instance = new ClipboardHistory();
}
return instance;
}
/**
* Returns the clipboard history, in most-recently-used order.
*
* @return The clipboard history.
*/
public List getHistory() {
List copy = new ArrayList<>(this.history);
Collections.reverse(copy);
return copy;
}
/**
* Returns the maximum number of clipboard values remembered.
*
* @return The maximum number of clipboard values remembered.
* @see #setMaxSize(int)
*/
public int getMaxSize() {
return maxSize;
}
/**
* Sets the maximum number of clipboard values remembered.
*
* @param maxSize The maximum number of clipboard values to remember.
* @throws IllegalArgumentException If maxSize is not greater
* than zero.
* @see #getMaxSize()
*/
public void setMaxSize(int maxSize) {
if (maxSize<=0) {
throw new IllegalArgumentException("Maximum size must be >= 0");
}
this.maxSize = maxSize;
trim();
}
/**
* Ensures the remembered set of strings is not larger than the maximum
* allowed size.
*/
private void trim() {
while (history.size()>maxSize) {
history.remove(0);
}
}
}