JDK14/Java14源码在线阅读
/*
* Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package javax.swing;
import java.io.*;
import java.awt.BorderLayout;
import java.awt.Frame;
import java.awt.Dialog;
import java.awt.Window;
import java.awt.Component;
import java.awt.Container;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.awt.event.WindowListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.IllegalComponentStateException;
import java.awt.Point;
import java.awt.Rectangle;
import java.text.*;
import java.util.Locale;
import javax.accessibility.*;
import javax.swing.event.*;
import javax.swing.text.*;
/** A class to monitor the progress of some operation. If it looks
* like the operation will take a while, a progress dialog will be popped up.
* When the ProgressMonitor is created it is given a numeric range and a
* descriptive string. As the operation progresses, call the setProgress method
* to indicate how far along the [min,max] range the operation is.
* Initially, there is no ProgressDialog. After the first millisToDecideToPopup
* milliseconds (default 500) the progress monitor will predict how long
* the operation will take. If it is longer than millisToPopup (default 2000,
* 2 seconds) a ProgressDialog will be popped up.
* <p>
* From time to time, when the Dialog box is visible, the progress bar will
* be updated when setProgress is called. setProgress won't always update
* the progress bar, it will only be done if the amount of progress is
* visibly significant.
*
* <p>
*
* For further documentation and examples see
* <a
href="https://docs.oracle.com/javase/tutorial/uiswing/components/progress.html">How to Monitor Progress</a>,
* a section in <em>The Java Tutorial.</em>
*
* @see ProgressMonitorInputStream
* @author James Gosling
* @author Lynn Monsanto (accessibility)
* @since 1.2
*/
public class ProgressMonitor implements Accessible
{
private ProgressMonitor root;
private JDialog dialog;
private JOptionPane pane;
private JProgressBar myBar;
private JLabel noteLabel;
private Component parentComponent;
private String note;
private Object[] cancelOption = null;
private Object message;
private long T0;
private int millisToDecideToPopup = 500;
private int millisToPopup = 2000;
private int min;
private int max;
/**
* Constructs a graphic object that shows progress, typically by filling
* in a rectangular bar as the process nears completion.
*
* @param parentComponent the parent component for the dialog box
* @param message a descriptive message that will be shown
* to the user to indicate what operation is being monitored.
* This does not change as the operation progresses.
* See the message parameters to methods in
* {@link JOptionPane#message}
* for the range of values.
* @param note a short note describing the state of the
* operation. As the operation progresses, you can call
* setNote to change the note displayed. This is used,
* for example, in operations that iterate through a
* list of files to show the name of the file being processes.
* If note is initially null, there will be no note line
* in the dialog box and setNote will be ineffective
* @param min the lower bound of the range
* @param max the upper bound of the range
* @see JDialog
* @see JOptionPane
*/
public ProgressMonitor(Component parentComponent,
Object message,
String note,
int min,
int max) {
this(parentComponent, message, note, min, max, null);
}
private ProgressMonitor(Component parentComponent,
Object message,
String note,
int min,
int max,
ProgressMonitor group) {
this.min = min;
this.max = max;
this.parentComponent = parentComponent;
cancelOption = new Object[1];
cancelOption[0] = UIManager.getString("OptionPane.cancelButtonText");
this.message = message;
this.note = note;
if (group != null) {
root = (group.root != null) ? group.root : group;
T0 = root.T0;
dialog = root.dialog;
}
else {
T0 = System.currentTimeMillis();
}
}
@SuppressWarnings("serial") // Superclass is not serializable across versions
private class ProgressOptionPane extends JOptionPane
{
ProgressOptionPane(Object messageList) {
super(messageList,
JOptionPane.INFORMATION_MESSAGE,
JOptionPane.DEFAULT_OPTION,
null,
ProgressMonitor.this.cancelOption,
null);
}
public int getMaxCharactersPerLineCount() {
return 60;
}
// Equivalent to JOptionPane.createDialog,
// but create a modeless dialog.
// This is necessary because the Solaris implementation doesn't
// support Dialog.setModal yet.
public JDialog createDialog(Component parentComponent, String title) {
final JDialog dialog;
Window window = JOptionPane.getWindowForComponent(parentComponent);
if (window instanceof Frame) {
dialog = new JDialog((Frame)window, title, false);
} else {
dialog = new JDialog((Dialog)window, title, false);
}
if (window instanceof SwingUtilities.SharedOwnerFrame) {
WindowListener ownerShutdownListener =
SwingUtilities.getSharedOwnerFrameShutdownListener();
dialog.addWindowListener(ownerShutdownListener);
}
Container contentPane = dialog.getContentPane();
contentPane.setLayout(new BorderLayout());
contentPane.add(this, BorderLayout.CENTER);
dialog.pack();
dialog.setLocationRelativeTo(parentComponent);
dialog.addWindowListener(new WindowAdapter() {
boolean gotFocus = false;
public void windowClosing(WindowEvent we) {
setValue(cancelOption[0]);
}
public void windowActivated(WindowEvent we) {
// Once window gets focus, set initial focus
if (!gotFocus) {
selectInitialValue();
gotFocus = true;
}
}
});
addPropertyChangeListener(new PropertyChangeListener() {
public void propertyChange(PropertyChangeEvent event) {
if(dialog.isVisible() &&
event.getSource() == ProgressOptionPane.this &&
(event.getPropertyName().equals(VALUE_PROPERTY) ||
event.getPropertyName().equals(INPUT_VALUE_PROPERTY))){
dialog.setVisible(false);
dialog.dispose();
}
}
});
return dialog;
}
/////////////////
// Accessibility support for ProgressOptionPane
////////////////
/**
* Gets the AccessibleContext for the ProgressOptionPane
*
* @return the AccessibleContext for the ProgressOptionPane
* @since 1.5
*/
public AccessibleContext getAccessibleContext() {
return ProgressMonitor.this.getAccessibleContext();
}
/*
* Returns the AccessibleJOptionPane
*/
private AccessibleContext getAccessibleJOptionPane() {
return super.getAccessibleContext();
}
}
/**
* Indicate the progress of the operation being monitored.
* If the specified value is >= the maximum, the progress
* monitor is closed.
* @param nv an int specifying the current value, between the
* maximum and minimum specified for this component
* @see #setMinimum
* @see #setMaximum
* @see #close
*/
@SuppressWarnings("deprecation")
public void setProgress(int nv) {
if (nv >= max) {
close();
}
else {
if (myBar != null) {
myBar.setValue(nv);
}
else {
long T = System.currentTimeMillis();
long dT = (int)(T-T0);
if (dT >= millisToDecideToPopup) {
int predictedCompletionTime;
if (nv > min) {
predictedCompletionTime = (int)(dT *
(max - min) /
(nv - min));
}
else {
predictedCompletionTime = millisToPopup;
}
if (predictedCompletionTime >= millisToPopup) {
myBar = new JProgressBar();
myBar.setMinimum(min);
myBar.setMaximum(max);
myBar.setValue(nv);
if (note != null) noteLabel = new JLabel(note);
pane = new ProgressOptionPane(new Object[] {message,
noteLabel,
myBar});
dialog = pane.createDialog(parentComponent,
UIManager.getString(
"ProgressMonitor.progressText"));
dialog.show();
}
}
}
}
}
/**
* Indicate that the operation is complete. This happens automatically
* when the value set by setProgress is >= max, but it may be called
* earlier if the operation ends early.
*/
public void close() {
if (dialog != null) {
dialog.setVisible(false);
dialog.dispose();
dialog = null;
pane = null;
myBar = null;
}
}
/**
* Returns the minimum value -- the lower end of the progress value.
*
* @return an int representing the minimum value
* @see #setMinimum
*/
public int getMinimum() {
return min;
}
/**
* Specifies the minimum value.
*
* @param m an int specifying the minimum value
* @see #getMinimum
*/
public void setMinimum(int m) {
if (myBar != null) {
myBar.setMinimum(m);
}
min = m;
}
/**
* Returns the maximum value -- the higher end of the progress value.
*
* @return an int representing the maximum value
* @see #setMaximum
*/
public int getMaximum() {
return max;
}
/**
* Specifies the maximum value.
*
* @param m an int specifying the maximum value
* @see #getMaximum
*/
public void setMaximum(int m) {
if (myBar != null) {
myBar.setMaximum(m);
}
max = m;
}
/**
* Returns true if the user hits the Cancel button or closes
* the progress dialog.
*
* @return true if the user hits the Cancel button or closes
* the progress dialog
*/
public boolean isCanceled() {
if (pane == null) {
return false;
}
Object v = pane.getValue();
if (v == null) {
return false;
}
return (((cancelOption.length == 1) && v.equals(cancelOption[0])) ||
v.equals(Integer.valueOf(JOptionPane.CLOSED_OPTION)));
}
/**
* Specifies the amount of time to wait before deciding whether or
* not to popup a progress monitor.
*
* @param millisToDecideToPopup an int specifying the time to wait,
* in milliseconds
* @see #getMillisToDecideToPopup
*/
public void setMillisToDecideToPopup(int millisToDecideToPopup) {
this.millisToDecideToPopup = millisToDecideToPopup;
}
/**
* Returns the amount of time this object waits before deciding whether
* or not to popup a progress monitor.
*
* @return the amount of time in milliseconds this object waits before
* deciding whether or not to popup a progress monitor
* @see #setMillisToDecideToPopup
*/
public int getMillisToDecideToPopup() {
return millisToDecideToPopup;
}
/**
* Specifies the amount of time it will take for the popup to appear.
* (If the predicted time remaining is less than this time, the popup
* won't be displayed.)
*
* @param millisToPopup an int specifying the time in milliseconds
* @see #getMillisToPopup
*/
public void setMillisToPopup(int millisToPopup) {
this.millisToPopup = millisToPopup;
}
/**
* Returns the amount of time it will take for the popup to appear.
*
* @return the amont of time in milliseconds it will take for the
* popup to appear
* @see #setMillisToPopup
*/
public int getMillisToPopup() {
return millisToPopup;
}
/**
* Specifies the additional note that is displayed along with the
* progress message. Used, for example, to show which file the
* is currently being copied during a multiple-file copy.
*
* @param note a String specifying the note to display
* @see #getNote
*/
public void setNote(String note) {
this.note = note;
if (noteLabel != null) {
noteLabel.setText(note);
}
}
/**
* Specifies the additional note that is displayed along with the
* progress message.
*
* @return a String specifying the note to display
* @see #setNote
*/
public String getNote() {
return note;
}
/////////////////
// Accessibility support
////////////////
/**
* The <code>AccessibleContext</code> for the <code>ProgressMonitor</code>
* @since 1.5
*/
protected AccessibleContext accessibleContext = null;
private AccessibleContext accessibleJOptionPane = null;
/**
* Gets the <code>AccessibleContext</code> for the
* <code>ProgressMonitor</code>
*
* @return the <code>AccessibleContext</code> for the
* <code>ProgressMonitor</code>
* @since 1.5
*/
public AccessibleContext getAccessibleContext() {
if (accessibleContext == null) {
accessibleContext = new AccessibleProgressMonitor();
}
if (pane != null && accessibleJOptionPane == null) {
// Notify the AccessibleProgressMonitor that the
// ProgressOptionPane was created. It is necessary
// to poll for ProgressOptionPane creation because
// the ProgressMonitor does not have a Component
// to add a listener to until the ProgressOptionPane
// is created.
if (accessibleContext instanceof AccessibleProgressMonitor) {
((AccessibleProgressMonitor)accessibleContext).optionPaneCreated();
}
}
return accessibleContext;
}
/**
* <code>AccessibleProgressMonitor</code> implements accessibility
* support for the <code>ProgressMonitor</code> class.
* @since 1.5
*/
protected class AccessibleProgressMonitor extends AccessibleContext
implements AccessibleText, ChangeListener, PropertyChangeListener {
/*
* The accessibility hierarchy for ProgressMonitor is a flattened
* version of the ProgressOptionPane component hierarchy.
*
* The ProgressOptionPane component hierarchy is:
* JDialog
* ProgressOptionPane
* JPanel
* JPanel
* JLabel
* JLabel
* JProgressBar
*
* The AccessibleProgessMonitor accessibility hierarchy is:
* AccessibleJDialog
* AccessibleProgressMonitor
* AccessibleJLabel
* AccessibleJLabel
* AccessibleJProgressBar
*
* The abstraction presented to assitive technologies by
* the AccessibleProgressMonitor is that a dialog contains a
* progress monitor with three children: a message, a note
* label and a progress bar.
*/
private Object oldModelValue;
/**
* AccessibleProgressMonitor constructor
*/
protected AccessibleProgressMonitor() {
}
/*
* Initializes the AccessibleContext now that the ProgressOptionPane
* has been created. Because the ProgressMonitor is not a Component
* implementing the Accessible interface, an AccessibleContext
* must be synthesized from the ProgressOptionPane and its children.
*
* For other AWT and Swing classes, the inner class that implements
* accessibility for the class extends the inner class that implements
* implements accessibility for the super class. AccessibleProgressMonitor
* cannot extend AccessibleJOptionPane and must therefore delegate calls
* to the AccessibleJOptionPane.
*/
private void optionPaneCreated() {
accessibleJOptionPane =
((ProgressOptionPane)pane).getAccessibleJOptionPane();
// add a listener for progress bar ChangeEvents
if (myBar != null) {
myBar.addChangeListener(this);
}
// add a listener for note label PropertyChangeEvents
if (noteLabel != null) {
noteLabel.addPropertyChangeListener(this);
}
}
/**
* Invoked when the target of the listener has changed its state.
*
* @param e a <code>ChangeEvent</code> object. Must not be null.
* @throws NullPointerException if the parameter is null.
*/
public void stateChanged(ChangeEvent e) {
if (e == null) {
return;
}
if (myBar != null) {
// the progress bar value changed
Object newModelValue = myBar.getValue();
firePropertyChange(ACCESSIBLE_VALUE_PROPERTY,
oldModelValue,
newModelValue);
oldModelValue = newModelValue;
}
}
/**
* This method gets called when a bound property is changed.
*
* @param e A <code>PropertyChangeEvent</code> object describing
* the event source and the property that has changed. Must not be null.
* @throws NullPointerException if the parameter is null.
*/
public void propertyChange(PropertyChangeEvent e) {
if (e.getSource() == noteLabel && e.getPropertyName() == "text") {
// the note label text changed
firePropertyChange(ACCESSIBLE_TEXT_PROPERTY, null, 0);
}
}
/* ===== Begin AccessileContext ===== */
/**
* Gets the accessibleName property of this object. The accessibleName
* property of an object is a localized String that designates the purpose
* of the object. For example, the accessibleName property of a label
* or button might be the text of the label or button itself. In the
* case of an object that doesn't display its name, the accessibleName
* should still be set. For example, in the case of a text field used
* to enter the name of a city, the accessibleName for the en_US locale
* could be 'city.'
*
* @return the localized name of the object; null if this
* object does not have a name
*
* @see #setAccessibleName
*/
public String getAccessibleName() {
if (accessibleName != null) { // defined in AccessibleContext
return accessibleName;
} else if (accessibleJOptionPane != null) {
// delegate to the AccessibleJOptionPane
return accessibleJOptionPane.getAccessibleName();
}
return null;
}
/**
* Gets the accessibleDescription property of this object. The
* accessibleDescription property of this object is a short localized
* phrase describing the purpose of the object. For example, in the
* case of a 'Cancel' button, the accessibleDescription could be
* 'Ignore changes and close dialog box.'
*
* @return the localized description of the object; null if
* this object does not have a description
*
* @see #setAccessibleDescription
*/
public String getAccessibleDescription() {
if (accessibleDescription != null) { // defined in AccessibleContext
return accessibleDescription;
} else if (accessibleJOptionPane != null) {
// delegate to the AccessibleJOptionPane
return accessibleJOptionPane.getAccessibleDescription();
}
return null;
}
/**
* Gets the role of this object. The role of the object is the generic
* purpose or use of the class of this object. For example, the role
* of a push button is AccessibleRole.PUSH_BUTTON. The roles in
* AccessibleRole are provided so component developers can pick from
* a set of predefined roles. This enables assistive technologies to
* provide a consistent interface to various tweaked subclasses of
* components (e.g., use AccessibleRole.PUSH_BUTTON for all components
* that act like a push button) as well as distinguish between subclasses
* that behave differently (e.g., AccessibleRole.CHECK_BOX for check boxes
* and AccessibleRole.RADIO_BUTTON for radio buttons).
* <p>Note that the AccessibleRole class is also extensible, so
* custom component developers can define their own AccessibleRole's
* if the set of predefined roles is inadequate.
*
* @return an instance of AccessibleRole describing the role of the object
* @see AccessibleRole
*/
public AccessibleRole getAccessibleRole() {
return AccessibleRole.PROGRESS_MONITOR;
}
/**
* Gets the state set of this object. The AccessibleStateSet of an object
* is composed of a set of unique AccessibleStates. A change in the
* AccessibleStateSet of an object will cause a PropertyChangeEvent to
* be fired for the ACCESSIBLE_STATE_PROPERTY property.
*
* @return an instance of AccessibleStateSet containing the
* current state set of the object
* @see AccessibleStateSet
* @see AccessibleState
* @see #addPropertyChangeListener
*/
public AccessibleStateSet getAccessibleStateSet() {
if (accessibleJOptionPane != null) {
// delegate to the AccessibleJOptionPane
return accessibleJOptionPane.getAccessibleStateSet();
}
return null;
}
/**
* Gets the Accessible parent of this object.
*
* @return the Accessible parent of this object; null if this
* object does not have an Accessible parent
*/
public Accessible getAccessibleParent() {
return dialog;
}
/*
* Returns the parent AccessibleContext
*/
private AccessibleContext getParentAccessibleContext() {
if (dialog != null) {
return dialog.getAccessibleContext();
}
return null;
}
/**
* Gets the 0-based index of this object in its accessible parent.
*
* @return the 0-based index of this object in its parent; -1 if this
* object does not have an accessible parent.
*
* @see #getAccessibleParent
* @see #getAccessibleChildrenCount
* @see #getAccessibleChild
*/
public int getAccessibleIndexInParent() {
if (accessibleJOptionPane != null) {
// delegate to the AccessibleJOptionPane
return accessibleJOptionPane.getAccessibleIndexInParent();
}
return -1;
}
/**
* Returns the number of accessible children of the object.
*
* @return the number of accessible children of the object.
*/
public int getAccessibleChildrenCount() {
// return the number of children in the JPanel containing
// the message, note label and progress bar
AccessibleContext ac = getPanelAccessibleContext();
if (ac != null) {
return ac.getAccessibleChildrenCount();
}
return 0;
}
/**
* Returns the specified Accessible child of the object. The Accessible
* children of an Accessible object are zero-based, so the first child
* of an Accessible child is at index 0, the second child is at index 1,
* and so on.
*
* @param i zero-based index of child
* @return the Accessible child of the object
* @see #getAccessibleChildrenCount
*/
public Accessible getAccessibleChild(int i) {
// return a child in the JPanel containing the message, note label
// and progress bar
AccessibleContext ac = getPanelAccessibleContext();
if (ac != null) {
return ac.getAccessibleChild(i);
}
return null;
}
/*
* Returns the AccessibleContext for the JPanel containing the
* message, note label and progress bar
*/
private AccessibleContext getPanelAccessibleContext() {
if (myBar != null) {
Component c = myBar.getParent();
if (c instanceof Accessible) {
return c.getAccessibleContext();
}
}
return null;
}
/**
* Gets the locale of the component. If the component does not have a
* locale, then the locale of its parent is returned.
*
* @return this component's locale. If this component does not have
* a locale, the locale of its parent is returned.
*
* @exception IllegalComponentStateException
* If the Component does not have its own locale and has not yet been
* added to a containment hierarchy such that the locale can be
* determined from the containing parent.
*/
public Locale getLocale() throws IllegalComponentStateException {
if (accessibleJOptionPane != null) {
// delegate to the AccessibleJOptionPane
return accessibleJOptionPane.getLocale();
}
return null;
}
/* ===== end AccessibleContext ===== */
/**
* Gets the AccessibleComponent associated with this object that has a
* graphical representation.
*
* @return AccessibleComponent if supported by object; else return null
* @see AccessibleComponent
*/
public AccessibleComponent getAccessibleComponent() {
if (accessibleJOptionPane != null) {
// delegate to the AccessibleJOptionPane
return accessibleJOptionPane.getAccessibleComponent();
}
return null;
}
/**
* Gets the AccessibleValue associated with this object that supports a
* Numerical value.
*
* @return AccessibleValue if supported by object; else return null
* @see AccessibleValue
*/
public AccessibleValue getAccessibleValue() {
if (myBar != null) {
// delegate to the AccessibleJProgressBar
return myBar.getAccessibleContext().getAccessibleValue();
}
return null;
}
/**
* Gets the AccessibleText associated with this object presenting
* text on the display.
*
* @return AccessibleText if supported by object; else return null
* @see AccessibleText
*/
public AccessibleText getAccessibleText() {
if (getNoteLabelAccessibleText() != null) {
return this;
}
return null;
}
/*
* Returns the note label AccessibleText
*/
private AccessibleText getNoteLabelAccessibleText() {
if (noteLabel != null) {
// AccessibleJLabel implements AccessibleText if the
// JLabel contains HTML text
return noteLabel.getAccessibleContext().getAccessibleText();
}
return null;
}
/* ===== Begin AccessibleText impl ===== */
/**
* Given a point in local coordinates, return the zero-based index
* of the character under that Point. If the point is invalid,
* this method returns -1.
*
* @param p the Point in local coordinates
* @return the zero-based index of the character under Point p; if
* Point is invalid return -1.
*/
public int getIndexAtPoint(Point p) {
AccessibleText at = getNoteLabelAccessibleText();
if (at != null && sameWindowAncestor(pane, noteLabel)) {
// convert point from the option pane bounds
// to the note label bounds.
Point noteLabelPoint = SwingUtilities.convertPoint(pane,
p,
noteLabel);
if (noteLabelPoint != null) {
return at.getIndexAtPoint(noteLabelPoint);
}
}
return -1;
}
/**
* Determines the bounding box of the character at the given
* index into the string. The bounds are returned in local
* coordinates. If the index is invalid an empty rectangle is returned.
*
* @param i the index into the String
* @return the screen coordinates of the character's bounding box,
* if index is invalid return an empty rectangle.
*/
public Rectangle getCharacterBounds(int i) {
AccessibleText at = getNoteLabelAccessibleText();
if (at != null && sameWindowAncestor(pane, noteLabel)) {
// return rectangle in the option pane bounds
Rectangle noteLabelRect = at.getCharacterBounds(i);
if (noteLabelRect != null) {
return SwingUtilities.convertRectangle(noteLabel,
noteLabelRect,
pane);
}
}
return null;
}
/*
* Returns whether source and destination components have the
* same window ancestor
*/
private boolean sameWindowAncestor(Component src, Component dest) {
if (src == null || dest == null) {
return false;
}
return SwingUtilities.getWindowAncestor(src) ==
SwingUtilities.getWindowAncestor(dest);
}
/**
* Returns the number of characters (valid indicies)
*
* @return the number of characters
*/
public int getCharCount() {
AccessibleText at = getNoteLabelAccessibleText();
if (at != null) { // JLabel contains HTML text
return at.getCharCount();
}
return -1;
}
/**
* Returns the zero-based offset of the caret.
*
* Note: That to the right of the caret will have the same index
* value as the offset (the caret is between two characters).
* @return the zero-based offset of the caret.
*/
public int getCaretPosition() {
AccessibleText at = getNoteLabelAccessibleText();
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