Cleanup in ImportCompletionProposal

The superclass BasicCompletionProposal already provides all necessary
behavior.

org.scala-ide.sdt.core/src/org/scalaide/core/internal/quickfix/ImportCompletionProposal.scala

@@ -1,30 +1,31 @@
 package org.scalaide.core.internal.quickfix
 
 import scala.tools.refactoring.implementations.AddImportStatement
-import org.scalaide.util.internal.eclipse.TextEditUtils
+
 import org.eclipse.jdt.ui.ISharedImages
 import org.eclipse.jdt.ui.JavaUI
-import org.eclipse.jdt.ui.text.java.IJavaCompletionProposal
 import org.eclipse.jface.text.IDocument
 import org.eclipse.jface.text.TextUtilities
-import org.eclipse.jface.text.contentassist.IContextInformation
-import org.eclipse.swt.graphics.Image
-import org.eclipse.swt.graphics.Point
+import org.scalaide.core.compiler.IScalaPresentationCompiler.Implicits._
 import org.scalaide.core.completion.RelevanceValues
+import org.scalaide.core.quickassist.BasicCompletionProposal
 import org.scalaide.logging.HasLogger
 import org.scalaide.util.eclipse.EditorUtils
-import org.scalaide.core.compiler.IScalaPresentationCompiler.Implicits._
-
-case class ImportCompletionProposal(val importName: String) extends IJavaCompletionProposal with HasLogger {
+import org.scalaide.util.internal.eclipse.TextEditUtils
 
-  def getRelevance() = RelevanceValues.ImportCompletionProposal
+case class ImportCompletionProposal(val importName: String)
+    extends BasicCompletionProposal(
+        relevance = RelevanceValues.ImportCompletionProposal,
+        displayString = s"Import $importName",
+        image = JavaUI.getSharedImages().getImage(ISharedImages.IMG_OBJS_IMPDECL))
+    with HasLogger {
 
   /**
    * Inserts the proposed completion into the given document.
    *
    * @param document the document into which to insert the proposed completion
    */
-  def apply(document: IDocument) {
+  override def apply(document: IDocument): Unit = {
     // First, try to insert with an AST transformation, if that fails, use the (old) method
     try {
       applyByASTTransformation(document)
@@ -41,7 +42,7 @@ case class ImportCompletionProposal(val importName: String) extends IJavaComplet
    *
    * @param document the document into which to insert the proposed completion
    */
-  private def applyByASTTransformation(document: IDocument) {
+  private def applyByASTTransformation(document: IDocument): Unit = {
 
     EditorUtils.withScalaFileAndSelection { (scalaSourceFile, textSelection) =>
 
@@ -72,7 +73,7 @@ case class ImportCompletionProposal(val importName: String) extends IJavaComplet
    *
    * @param document the document into which to insert the proposed completion
    */
-  private def applyByTextTransformation(document: IDocument) {
+  private def applyByTextTransformation(document: IDocument): Unit = {
     val lineDelimiter = TextUtilities.getDefaultLineDelimiter(document)
 
     // Find the package declaration
@@ -111,61 +112,4 @@ case class ImportCompletionProposal(val importName: String) extends IJavaComplet
     // Insert the import as the third line in the file... RISKY AS HELL :D
     document.replace(insertIndex, 0, preInsert + "import " + importName + lineDelimiter);
   }
-
-  /**
-   * Returns the new selection after the proposal has been applied to
-   * the given document in absolute document coordinates. If it returns
-   * <code>null</code>, no new selection is set.
-   *
-   * A document change can trigger other document changes, which have
-   * to be taken into account when calculating the new selection. Typically,
-   * this would be done by installing a document listener or by using a
-   * document position during {@link #apply(IDocument)}.
-   *
-   * @param document the document into which the proposed completion has been inserted
-   * @return the new selection in absolute document coordinates
-   */
-  def getSelection(document: IDocument): Point = null
-
-
-  /**
-   * Returns optional additional information about the proposal. The additional information will
-   * be presented to assist the user in deciding if the selected proposal is the desired choice.
-   * <p>
-   * If {@link ICompletionProposalExtension5} is implemented, this method should not be called any
-   * longer. This method may be deprecated in a future release.
-   * </p>
-   *
-   * @return the additional information or <code>null</code>
-   */
-  def getAdditionalProposalInfo(): String = null
-
-
-  /**
-   * Returns the string to be displayed in the list of completion proposals.
-   *
-   * @return the string to be displayed
-   *
-   * @see ICompletionProposalExtension6#getStyledDisplayString()
-   */
-  def getDisplayString(): String = s"Import $importName"
-
-
-  /**
-   * Returns the image to be displayed in the list of completion proposals.
-   * The image would typically be shown to the left of the display string.
-   *
-   * @return the image to be shown or <code>null</code> if no image is desired
-   */
-  def getImage(): Image = JavaUI.getSharedImages().getImage(ISharedImages.IMG_OBJS_IMPDECL)
-
-
-  /**
-   * Returns optional context information associated with this proposal.
-   * The context information will automatically be shown if the proposal
-   * has been applied.
-   *
-   * @return the context information for this proposal or <code>null</code>
-   */
-  def getContextInformation(): IContextInformation = null
 }