Class AutoCompletion

  • Direct Known Subclasses:
    RoundRobinAutoCompletion

    public class AutoCompletion
    extends java.lang.Object
    Adds auto-completion to a text component. Provides a popup window with a list of auto-complete choices on a given keystroke, such as Ctrl+Space.

    Depending on the CompletionProvider installed, the following auto-completion features may be enabled:

    • An auto-complete choices list made visible via e.g. Ctrl+Space
    • A "description" window displayed alongside the choices list that provides documentation on the currently selected completion choice (as seen in Eclipse and NetBeans).
    • Parameter assistance. If this is enabled, if the user enters a "parameterized" completion, such as a method or a function, then they will receive a tool tip describing the arguments they have to enter to the completion. Also, the arguments can be navigated via tab and shift+tab (a la Eclipse and NetBeans).
    Version:
    1.0
    • Field Detail

      • textComponent

        private javax.swing.text.JTextComponent textComponent
        The text component we're providing completion for.
      • parentWindow

        private java.awt.Window parentWindow
        The parent window of textComponent.
      • preferredChoicesWindowSize

        private java.awt.Dimension preferredChoicesWindowSize
        The preferred size of the completion choices window. This field exists because the user will likely set the preferred size of the window before it is actually created.
      • preferredDescWindowSize

        private java.awt.Dimension preferredDescWindowSize
        The preferred size of the optional description window. This field only exists because the user may (and usually will) set the size of the description window before it exists (it must be parented to a Window).
      • descWindowColor

        private java.awt.Color descWindowColor
        The background color of the description window.
      • provider

        private CompletionProvider provider
        Provides the completion options relevant to the current caret position.
      • renderer

        private javax.swing.ListCellRenderer<java.lang.Object> renderer
        The renderer to use for the completion choices. If this is null, then a default renderer is used.
      • externalURLHandler

        private ExternalURLHandler externalURLHandler
        The handler to use when an external URL is clicked in the help documentation.
      • linkRedirector

        private static LinkRedirector linkRedirector
        An optional redirector that converts URL's to some other location before being handed over to externalURLHandler.
      • showDescWindow

        private boolean showDescWindow
        Whether the description window should be displayed along with the completion choice window.
      • autoCompleteEnabled

        private boolean autoCompleteEnabled
        Whether auto-complete is enabled.
      • autoActivationEnabled

        private boolean autoActivationEnabled
        Whether the auto-activation of auto-complete (after a delay, after the user types an appropriate character) is enabled.
      • autoCompleteSingleChoices

        private boolean autoCompleteSingleChoices
        Whether, when there is only a single auto-complete option that matches the text at the current text position, that text should be auto-inserted, instead of the completion window displaying.
      • parameterAssistanceEnabled

        private boolean parameterAssistanceEnabled
        Whether parameter assistance is enabled.
      • parameterDescriptionTruncateThreshold

        private int parameterDescriptionTruncateThreshold
        The maximum length to attempt to display the 'full' parameter description for before truncating.
      • paramChoicesRenderer

        private javax.swing.ListCellRenderer<java.lang.Object> paramChoicesRenderer
        A renderer used for Completions in the optional parameter choices popup window (displayed when a ParameterizedCompletion is code-completed). If this isn't set, a default renderer is used.
      • trigger

        private javax.swing.KeyStroke trigger
        The keystroke that triggers the completion window.
      • oldTriggerKey

        private java.lang.Object oldTriggerKey
        The previous key in the text component's InputMap for the trigger key.
      • oldTriggerAction

        private javax.swing.Action oldTriggerAction
        The action previously assigned to trigger, so we can reset it if the user disables auto-completion.
      • oldParenKey

        private java.lang.Object oldParenKey
        The previous key in the text component's InputMap for the parameter completion trigger key.
      • oldParenAction

        private javax.swing.Action oldParenAction
        The action previously assigned to the parameter completion key, so we can reset it when we uninstall.
      • parentWindowListener

        private AutoCompletion.ParentWindowListener parentWindowListener
        Listens for events in the parent window that affect the visibility of the popup windows.
      • textComponentListener

        private AutoCompletion.TextComponentListener textComponentListener
        Listens for events from the text component that affect the visibility of the popup windows.
      • autoActivationListener

        private AutoCompletion.AutoActivationListener autoActivationListener
        Listens for events in the text component that cause the popup windows to automatically activate.
      • listeners

        private javax.swing.event.EventListenerList listeners
        All listeners registered on this component.
      • hideOnNoText

        private boolean hideOnNoText
        Whether the popup should be hidden when user types a space (or any character that resets the completion list to "all completions"). Defaults to true.
      • hideOnCompletionProviderChange

        private boolean hideOnCompletionProviderChange
        Whether the popup should be hidden when the CompletionProvider changes. If set to false, caller has to ensure refresh of the popup content. Defaults to true.
      • PARAM_TRIGGER_KEY

        private static final java.lang.String PARAM_TRIGGER_KEY
        The key used in the input map for the AutoComplete action.
        See Also:
        Constant Field Values
      • PARAM_COMPLETE_KEY

        private static final java.lang.String PARAM_COMPLETE_KEY
        Key used in the input map for the parameter completion action.
        See Also:
        Constant Field Values
      • STYLE_CONTEXT

        private static final AutoCompletionStyleContext STYLE_CONTEXT
        Stores how to render auto-completion-specific highlights in text components.
      • DEBUG

        private static final boolean DEBUG
        Whether debug messages should be printed to stdout as AutoCompletion runs.
      • DOCUMENT_CHANGED_PROPERTY

        private static final java.lang.String DOCUMENT_CHANGED_PROPERTY
        Fired by JTextComponents when their Document changes.
        See Also:
        Constant Field Values
    • Constructor Detail

      • AutoCompletion

        public AutoCompletion​(CompletionProvider provider)
        Constructor.
        Parameters:
        provider - The completion provider. This cannot be null
    • Method Detail

      • doCompletion

        public void doCompletion()
        Displays the popup window. Hosting applications can call this method to programmatically begin an auto-completion operation.
      • getAutoActivationDelay

        public int getAutoActivationDelay()
        Returns the delay between when the user types a character and when the code completion popup should automatically appear (if applicable).
        Returns:
        The delay, in milliseconds.
        See Also:
        setAutoActivationDelay(int)
      • getAutoCompleteSingleChoices

        public boolean getAutoCompleteSingleChoices()
        Returns whether, if a single auto-complete choice is available, it should be automatically inserted, without displaying the popup menu.
        Returns:
        Whether to auto-complete single choices.
        See Also:
        setAutoCompleteSingleChoices(boolean)
      • getCompletionProvider

        public CompletionProvider getCompletionProvider()
        Returns the completion provider.
        Returns:
        The completion provider.
      • getDebug

        static boolean getDebug()
        Returns whether debug is enabled for AutoCompletion.
        Returns:
        Whether debug is enabled.
      • getDefaultTriggerKey

        public static javax.swing.KeyStroke getDefaultTriggerKey()
        Returns the default auto-complete "trigger key" for this OS. For Windows, for example, it is Ctrl+Space.
        Returns:
        The default auto-complete trigger key.
      • getLineOfCaret

        int getLineOfCaret()
      • getListCellRenderer

        public javax.swing.ListCellRenderer getListCellRenderer()
        Returns the default list cell renderer used when a completion provider does not supply its own.
        Returns:
        The default list cell renderer.
        See Also:
        setListCellRenderer(ListCellRenderer)
      • getReplacementText

        protected java.lang.String getReplacementText​(Completion c,
                                                      javax.swing.text.Document doc,
                                                      int start,
                                                      int len)
        Returns the text to replace with in the document. This is a "last-chance" hook for subclasses to make special modifications to the completion text inserted. The default implementation simply returns c.getReplacementText(). You usually will not need to modify this method.
        Parameters:
        c - The completion being inserted.
        doc - The document being modified.
        start - The start of the text being replaced.
        len - The length of the text being replaced.
        Returns:
        The text to replace with.
      • getShowDescWindow

        public boolean getShowDescWindow()
        Returns whether the "description window" should be shown alongside the completion window.
        Returns:
        Whether the description window should be shown.
        See Also:
        setShowDescWindow(boolean)
      • getStyleContext

        public static AutoCompletionStyleContext getStyleContext()
        Returns the style context describing how auto-completion related highlights in the editor are rendered.
        Returns:
        The style context.
      • getDescWindowColor

        public java.awt.Color getDescWindowColor()
        Returns the background color for the description window.
        Returns:
        The color.
      • getTextComponent

        public javax.swing.text.JTextComponent getTextComponent()
        Returns the text component for which auto-completion is enabled.
        Returns:
        The text component, or null if this AutoCompletion is not installed on any text component.
        See Also:
        install(JTextComponent)
      • getTextComponentOrientation

        java.awt.ComponentOrientation getTextComponentOrientation()
        Returns the orientation of the text component we're installed to.
        Returns:
        The orientation of the text component, or null if we are not installed on one.
      • getTriggerKey

        public javax.swing.KeyStroke getTriggerKey()
        Returns the "trigger key" used for auto-complete.
        Returns:
        The trigger key.
        See Also:
        setTriggerKey(KeyStroke)
      • hideChildWindows

        public boolean hideChildWindows()
        Hides any child windows being displayed by the auto-completion system.
        Returns:
        Whether any windows were visible.
      • hideParameterCompletionPopups

        private boolean hideParameterCompletionPopups()
        Hides and disposes of any parameter completion-related popups.
        Returns:
        Whether any such windows were visible (and thus hidden).
      • hidePopupWindow

        protected boolean hidePopupWindow()
        Hides the popup window, if it is visible.
        Returns:
        Whether the popup window was visible.
      • initDebug

        private static boolean initDebug()
        Determines whether debug should be enabled for the AutoCompletion library. This method checks a system property, but takes care of SecurityExceptions in case we're in an applet or WebStart.
        Returns:
        Whether debug should be enabled.
      • insertCompletion

        protected final void insertCompletion​(Completion c)
        Inserts a completion. Any time a code completion event occurs, the actual text insertion happens through this method.
        Parameters:
        c - A completion to insert. This cannot be null.
      • insertCompletion

        protected void insertCompletion​(Completion c,
                                        boolean typedParamListStartChar)
        Inserts a completion. Any time a code completion event occurs, the actual text insertion happens through this method.
        Parameters:
        c - A completion to insert. This cannot be null.
        typedParamListStartChar - Whether the parameterized completion start character was typed (typically '(').
      • install

        public void install​(javax.swing.text.JTextComponent c)
        Installs this auto-completion on a text component. If this AutoCompletion is already installed on another text component, it is uninstalled first.
        Parameters:
        c - The text component.
        See Also:
        uninstall()
      • installTriggerKey

        private void installTriggerKey​(javax.swing.KeyStroke ks)
        Installs a "trigger key" action onto the current text component.
        Parameters:
        ks - The keystroke that should trigger the action.
        See Also:
        uninstallTriggerKey()
      • createAutoCompleteAction

        protected javax.swing.Action createAutoCompleteAction()
        Creates and returns the action to call when the user presses the auto-completion trigger key (e.g. ctrl+space). This is a hook for subclasses that want to provide their own behavior in this scenario. The default implementation returns an AutoCompletion.AutoCompleteAction.
        Returns:
        The action to use.
        See Also:
        AutoCompletion.AutoCompleteAction
      • isAutoActivationEnabled

        public boolean isAutoActivationEnabled()
        Returns whether auto-activation is enabled (that is, whether the completion popup will automatically appear after a delay when the user types an appropriate character). Note that this parameter will be ignored if auto-completion is disabled.
        Returns:
        Whether auto-activation is enabled.
        See Also:
        setAutoActivationEnabled(boolean), getAutoActivationDelay(), isAutoCompleteEnabled()
      • isAutoCompleteEnabled

        public boolean isAutoCompleteEnabled()
        Returns whether auto-completion is enabled.
        Returns:
        Whether auto-completion is enabled.
        See Also:
        setAutoCompleteEnabled(boolean)
      • isHideOnCompletionProviderChange

        protected boolean isHideOnCompletionProviderChange()
        Whether the popup should be hidden when the CompletionProvider changes. If set to false, caller has to ensure refresh of the popup content.
        Returns:
        Whether the popup should be hidden when the completion provider changes.
        See Also:
        setHideOnCompletionProviderChange(boolean)
      • isHideOnNoText

        protected boolean isHideOnNoText()
        Whether the popup should be hidden when user types a space (or any character that resets the completion list to "all completions").
        Returns:
        Whether the popup should be hidden when the completion list is reset to show all completions.
        See Also:
        setHideOnNoText(boolean)
      • isParameterAssistanceEnabled

        public boolean isParameterAssistanceEnabled()
        Returns whether parameter assistance is enabled.
        Returns:
        Whether parameter assistance is enabled.
        See Also:
        setParameterAssistanceEnabled(boolean)
      • isPopupVisible

        public boolean isPopupVisible()
        Returns whether the completion popup window is visible.
        Returns:
        Whether the completion popup window is visible.
      • refreshPopupWindow

        protected int refreshPopupWindow()
        Refreshes the popup window. First, this method gets the possible completions for the current caret position. If there are none, and the popup is visible, it is hidden. If there are some completions and the popup is hidden, it is made visible and made to display the completions. If there are some completions and the popup is visible, its list is updated to the current set of completions.
        Returns:
        The current line number of the caret.
      • setAutoActivationDelay

        public void setAutoActivationDelay​(int ms)
        Sets the delay between when the user types a character and when the code completion popup should automatically appear (if applicable).
        Parameters:
        ms - The delay, in milliseconds. This should be greater than zero.
        See Also:
        getAutoActivationDelay()
      • setAutoActivationEnabled

        public void setAutoActivationEnabled​(boolean enabled)
        Toggles whether auto-activation is enabled. Note that auto-activation also depends on auto-completion itself being enabled.
        Parameters:
        enabled - Whether auto-activation is enabled.
        See Also:
        isAutoActivationEnabled(), setAutoActivationDelay(int)
      • setAutoCompleteEnabled

        public void setAutoCompleteEnabled​(boolean enabled)
        Sets whether auto-completion is enabled.
        Parameters:
        enabled - Whether auto-completion is enabled.
        See Also:
        isAutoCompleteEnabled()
      • setAutoCompleteSingleChoices

        public void setAutoCompleteSingleChoices​(boolean autoComplete)
        Sets whether, if a single auto-complete choice is available, it should be automatically inserted, without displaying the popup menu.
        Parameters:
        autoComplete - Whether to auto-complete single choices.
        See Also:
        getAutoCompleteSingleChoices()
      • setCompletionProvider

        public void setCompletionProvider​(CompletionProvider provider)
        Sets the completion provider being used.
        Parameters:
        provider - The new completion provider. This cannot be null.
        Throws:
        java.lang.IllegalArgumentException - If provider is null.
      • setChoicesWindowSize

        public void setChoicesWindowSize​(int w,
                                         int h)
        Sets the size of the completion choices window.
        Parameters:
        w - The new width.
        h - The new height.
        See Also:
        setDescriptionWindowSize(int, int)
      • setDescriptionWindowSize

        public void setDescriptionWindowSize​(int w,
                                             int h)
        Sets the size of the description window.
        Parameters:
        w - The new width.
        h - The new height.
        See Also:
        setChoicesWindowSize(int, int)
      • setDescriptionWindowColor

        public void setDescriptionWindowColor​(java.awt.Color c)
        Sets the color of the description window.
        Parameters:
        c - The new color.
      • setExternalURLHandler

        public void setExternalURLHandler​(ExternalURLHandler handler)
        Sets the handler to use when an external URL is clicked in the description window. This handler can perform some action, such as open the URL in a web browser. The default implementation will open the URL in a browser, but only if running in Java 6. If you want browser support for Java 5 and below, or otherwise want to respond to hyperlink clicks, you will have to install your own handler to do so.
        Parameters:
        handler - The new handler.
        See Also:
        getExternalURLHandler()
      • setHideOnCompletionProviderChange

        protected void setHideOnCompletionProviderChange​(boolean hideOnCompletionProviderChange)
        Sets whether the popup should be hidden when the CompletionProvider changes. If set to false, caller has to ensure refresh of the popup content.
        Parameters:
        hideOnCompletionProviderChange - Whether the popup should be hidden when the completion provider changes.
        See Also:
        isHideOnCompletionProviderChange()
      • setHideOnNoText

        protected void setHideOnNoText​(boolean hideOnNoText)
        Sets whether the popup should be hidden when user types a space (or any character that resets the completion list to "all completions").
        Parameters:
        hideOnNoText - Whether the popup should be hidden when the completion list is reset to show all completions.
        See Also:
        isHideOnNoText()
      • setLinkRedirector

        public static void setLinkRedirector​(LinkRedirector linkRedirector)
        Sets the redirector for external URL's found in code completion documentation. When a non-local link in completion popups is clicked, this redirector is given the chance to modify the URL fetched and displayed.
        Parameters:
        linkRedirector - The link redirector, or null for none.
        See Also:
        getLinkRedirector()
      • setListCellRenderer

        public void setListCellRenderer​(javax.swing.ListCellRenderer<java.lang.Object> renderer)
        Sets the default list cell renderer to use when a completion provider does not supply its own.
        Parameters:
        renderer - The renderer to use. If this is null, a default renderer is used.
        See Also:
        getListCellRenderer()
      • setParameterAssistanceEnabled

        public void setParameterAssistanceEnabled​(boolean enabled)
        Sets whether parameter assistance is enabled. If parameter assistance is enabled, and a "parameterized" completion (such as a function or method) is inserted, the user will get "assistance" in inserting the parameters in the form of a popup window with documentation and easy tabbing through the arguments (as seen in Eclipse and NetBeans).
        Parameters:
        enabled - Whether parameter assistance should be enabled.
        See Also:
        isParameterAssistanceEnabled()
      • setPopupVisible

        protected void setPopupVisible​(boolean visible)
        Toggles the visibility of the auto-completion popup window. This fires an AutoCompletionEvent of the appropriate type.
        Parameters:
        visible - Whether the window should be made visible or hidden.
        See Also:
        isPopupVisible()
      • setShowDescWindow

        public void setShowDescWindow​(boolean show)
        Sets whether the "description window" should be shown beside the completion window.
        Parameters:
        show - Whether to show the description window.
        See Also:
        getShowDescWindow()
      • setTriggerKey

        public void setTriggerKey​(javax.swing.KeyStroke ks)
        Sets the keystroke that should be used to trigger the auto-complete popup window.
        Parameters:
        ks - The keystroke.
        Throws:
        java.lang.IllegalArgumentException - If ks is null.
        See Also:
        getTriggerKey()
      • startParameterizedCompletionAssistance

        private void startParameterizedCompletionAssistance​(ParameterizedCompletion pc,
                                                            boolean typedParamListStartChar)
        Displays a "tool tip" detailing the inputs to the function just entered.
        Parameters:
        pc - The completion.
        typedParamListStartChar - Whether the parameterized completion list starting character was typed.
      • uninstall

        public void uninstall()
        Uninstalls this auto-completion from its text component. If it is not installed on any text component, nothing happens.
        See Also:
        install(JTextComponent)
      • uninstallTriggerKey

        private void uninstallTriggerKey()
        Replaces the "trigger key" action with the one that was there before auto-completion was installed.
        See Also:
        installTriggerKey(KeyStroke)
      • updateUI

        private void updateUI()
        Updates the LookAndFeel of the popup window. Applications can call this method as appropriate if they support changing the LookAndFeel at runtime.
      • setParameterDescriptionTruncateThreshold

        public void setParameterDescriptionTruncateThreshold​(int truncateThreshold)
        Sets the maximum number of characters that the ParameterizedCompletionDescriptionToolTip will attempt to display on one line before truncating to a short-form representation.
        Parameters:
        truncateThreshold - The number of characters before truncation occurs.
        See Also:
        getParameterDescriptionTruncateThreshold()