74 lines
1.4 KiB
Java
74 lines
1.4 KiB
Java
package dev.kske.undoredo;
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import java.util.List;
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/**
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* A change manager keeps track of subsequent changes and allows un- and redoing them. A specific
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* change can be marked using {@link #mark()} to keep track of a saved state in the application that
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* uses the manager.
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*
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* @param <C> the change type to store in this change manager
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* @author Maximilian Käfer
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* @author Kai S. K. Engelbart
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* @since 0.0.1
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*/
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public interface ChangeManager<C extends Change> {
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/**
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* Applies the given change and appends it to the change list.
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*
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* @param change the change to add
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* @since 0.0.1
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*/
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void addChange(C change);
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/**
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* Undoes the current change.
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*
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* @return whether an action was performed
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* @since 0.1.0
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*/
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boolean undo();
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/**
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* Applies the change that was undone before.
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*
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* @return whether an action was performed
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* @since 0.0.1
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*/
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boolean redo();
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/**
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* Marks the current change.
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*
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* @since 0.0.1
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*/
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void mark();
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/**
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* @return whether the current change is marked
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* @since 0.0.1
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*/
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boolean isAtMarkedIndex();
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/**
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* @return whether a change is present that can be undone
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* @since 0.0.1
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*/
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boolean isUndoAvailable();
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/**
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* @return whether a change is present that can be redone
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* @since 0.0.1
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*/
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boolean isRedoAvailable();
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/**
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* Provides an unmodifiable view of the changes stored in this change manager.
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*
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* @return all stored changes
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* @since 0.0.1
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*/
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List<C> getChanges();
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}
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