refact: improve handling of arrays

org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/breakpoints/DSPBreakpointAdapter.java

@@ -33,8 +33,7 @@ public void toggleLineBreakpoints(IWorkbenchPart part, ISelection selection) thr
  int lineNumber = textSelection.getStartLine();
  IBreakpoint[] breakpoints = DebugPlugin.getDefault().getBreakpointManager()
  .getBreakpoints(DSPPlugin.ID_DSP_DEBUG_MODEL);
- for (int i = 0; i < breakpoints.length; i++) {
- IBreakpoint breakpoint = breakpoints[i];
+ for (final IBreakpoint breakpoint : breakpoints) {
  if (breakpoint instanceof ILineBreakpoint lineBreakpoint
  && resource.equals(breakpoint.getMarker().getResource())
  && lineBreakpoint.getLineNumber() == (lineNumber + 1)) {

org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/debugmodel/DSPDebugTarget.java

@@ -62,6 +62,7 @@
 import org.eclipse.lsp4e.debug.console.DSPProcess;
 import org.eclipse.lsp4e.debug.console.DSPStreamsProxy;
 import org.eclipse.lsp4e.debug.debugmodel.TransportStreams.DefaultTransportStreams;
+import org.eclipse.lsp4e.internal.ArrayUtil;
 import org.eclipse.lsp4j.debug.BreakpointEventArguments;
 import org.eclipse.lsp4j.debug.Capabilities;
 import org.eclipse.lsp4j.debug.ConfigurationDoneArguments;
@@ -313,13 +314,13 @@ private CompletableFuture<?> initialize(Map<String, Object> dspParameters, IProg
 
  private void terminated() {
  fTerminated = true;
- Arrays.stream(getThreads()).forEach(t -> {
+ for (final DSPThread t : getThreads()) {
  try {
  t.terminate();
  } catch (DebugException e) {
  DSPPlugin.logError(e);
  }
- });
+ }
  final var process = this.process;
  if (process != null && process.canTerminate()) {
  try {
@@ -452,7 +453,7 @@ public void continued(ContinuedEventArguments body) {
  DSPDebugElement source = null;
  source = getThread(body.getThreadId());
  if (source == null || body.getAllThreadsContinued() == null || body.getAllThreadsContinued()) {
- Arrays.asList(getThreads()).forEach(DSPThread::continued);
+ ArrayUtil.forEach(getThreads(), DSPThread::continued);
  }
  if (source != null) {
  source.fireResumeEvent(DebugEvent.CLIENT_REQUEST);
@@ -468,10 +469,10 @@ public void stopped(StoppedEventArguments body) {
  source = getThread(body.getThreadId());
  }
  if (source == null || body.getAllThreadsStopped() == null || body.getAllThreadsStopped()) {
- Arrays.asList(getThreads()).forEach(t -> {
+ for (final DSPThread t : getThreads()) {
  t.stopped();
  t.fireChangeEvent(DebugEvent.CHANGE);
- });
+ }
  }
 
  if (source != null) {
@@ -506,8 +507,7 @@ public boolean canSuspend() {
  @Override
  public boolean isSuspended() {
  DSPThread[] dspThreads = getThreads();
- boolean anyMatch = Arrays.asList(dspThreads).stream().anyMatch(DSPThread::isSuspended);
- return anyMatch;
+ return ArrayUtil.anyMatch(dspThreads, DSPThread::isSuspended);
  }
 
  @Override

org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/debugmodel/DSPStackFrame.java

@@ -26,6 +26,9 @@
 import org.eclipse.lsp4j.debug.StackFrame;
 
 public class DSPStackFrame extends DSPDebugElement implements IStackFrame {
+
+ private static final IRegisterGroup[] NO_REGISTER_GROUPS = new IRegisterGroup[0];
+
  private final DSPThread thread;
  private StackFrame stackFrame;
  private final int depth;
@@ -157,7 +160,7 @@ public DSPThread getThread() {
 
  @Override
  public IRegisterGroup[] getRegisterGroups() throws DebugException {
- return new IRegisterGroup[0];
+ return NO_REGISTER_GROUPS;
  }
 
  @Override

org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/debugmodel/DSPThread.java

@@ -25,6 +25,7 @@
 import org.eclipse.debug.core.model.IThread;
 import org.eclipse.jdt.annotation.Nullable;
 import org.eclipse.lsp4e.debug.DSPPlugin;
+import org.eclipse.lsp4e.internal.ArrayUtil;
 import org.eclipse.lsp4j.debug.ContinueArguments;
 import org.eclipse.lsp4j.debug.NextArguments;
 import org.eclipse.lsp4j.debug.PauseArguments;
@@ -35,6 +36,10 @@
 import org.eclipse.lsp4j.debug.Thread;
 
 public class DSPThread extends DSPDebugElement implements IThread {
+
+ private static final IStackFrame[] NO_STACK_FRAMES = new IStackFrame[0];
+ private static final IBreakpoint[] NO_BREAKPOINTS = new IBreakpoint[0];
+
  private final Integer id;
  /**
  * The name may not be known, if it is requested we will ask for it from the
@@ -221,18 +226,13 @@ public boolean hasStackFrames() throws DebugException {
 
  @Override
  public @Nullable IStackFrame getTopStackFrame() throws DebugException {
- IStackFrame[] stackFrames = getStackFrames();
- if (stackFrames.length > 0) {
- return stackFrames[0];
- } else {
- return null;
- }
+ return ArrayUtil.findFirst(getStackFrames());
  }
 
  @Override
  public IStackFrame[] getStackFrames() throws DebugException {
  if (!isSuspended()) {
- return new IStackFrame[0];
+ return NO_STACK_FRAMES;
  }
  if (!refreshFrames.getAndSet(false)) {
  synchronized (frames) {
@@ -263,12 +263,12 @@ public IStackFrame[] getStackFrames() throws DebugException {
  return future.get();
  } catch (RuntimeException | ExecutionException e) {
  if (isTerminated()) {
- return new DSPStackFrame[0];
+ return NO_STACK_FRAMES;
  }
  throw newTargetRequestFailedException(e.getMessage(), e);
  } catch (InterruptedException e) {
  java.lang.Thread.currentThread().interrupt();
- return new DSPStackFrame[0];
+ return NO_STACK_FRAMES;
  }
  }
 
@@ -291,7 +291,7 @@ public String getName() {
  @Override
  public IBreakpoint[] getBreakpoints() {
  // TODO update breakpoints from stopped messages from server
- return new IBreakpoint[0];
+ return NO_BREAKPOINTS;
  }
 
  public Integer getId() {

org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/debugmodel/DSPValue.java

@@ -19,6 +19,8 @@
 
 public final class DSPValue extends DSPDebugElement implements IValue {
 
+ private static final IVariable[] NO_VARIABLES = new IVariable[0];
+
  private final @Nullable DSPVariable modelVariable;
  private final Integer variablesReference;
  private final String value;
@@ -41,7 +43,7 @@ public DSPValue(DSPDebugTarget debugger, Integer variablesReference, String valu
  @Override
  public IVariable @Nullable [] getVariables() throws DebugException {
  if (!hasVariables()) {
- return new IVariable[0];
+ return NO_VARIABLES;
  }
  if (cachedVariables == null) {
  final var arguments = new VariablesArguments();

org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/launcher/DSPMainTab.java

@@ -11,7 +11,6 @@
 import static org.eclipse.lsp4e.internal.NullSafetyHelper.lateNonNull;
 import static org.eclipse.swt.events.SelectionListener.widgetSelectedAdapter;
 
-import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 
@@ -270,7 +269,7 @@ public void performApply(ILaunchConfigurationWorkingCopy configuration) {
  if (arg == null) {
  configuration.setAttribute(DSPPlugin.ATTR_DSP_ARGS, (String) null);
  } else {
- configuration.setAttribute(DSPPlugin.ATTR_DSP_ARGS, Arrays.asList(arg.split("\\s+"))); //$NON-NLS-1$
+ configuration.setAttribute(DSPPlugin.ATTR_DSP_ARGS, List.of(arg.split("\\s+"))); //$NON-NLS-1$
  }
  configuration.setAttribute(DSPPlugin.ATTR_DSP_MONITOR_DEBUG_ADAPTER,
  monitorAdapterLauncherProcessCheckbox.getSelection());

org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/presentation/DAPWatchExpression.java

@@ -8,6 +8,7 @@
  *******************************************************************************/
 package org.eclipse.lsp4e.debug.presentation;
 
+import static org.eclipse.lsp4e.internal.ArrayUtil.NO_STRINGS;
 import static org.eclipse.lsp4e.internal.NullSafetyHelper.castNonNull;
 
 import org.eclipse.core.runtime.Adapters;
@@ -21,6 +22,7 @@
 import org.eclipse.lsp4e.debug.debugmodel.DSPDebugTarget;
 import org.eclipse.lsp4e.debug.debugmodel.DSPStackFrame;
 import org.eclipse.lsp4e.debug.debugmodel.DSPValue;
+import org.eclipse.lsp4e.internal.ArrayUtil;
 import org.eclipse.lsp4j.debug.EvaluateArguments;
 import org.eclipse.lsp4j.debug.EvaluateResponse;
 
@@ -63,7 +65,7 @@ public String getExpressionText() {
 
  @Override
  public String[] getErrorMessages() {
- return new String[0];
+ return NO_STRINGS;
  }
  };
  }

org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/presentation/DSPDebugModelPresentation.java

@@ -98,8 +98,7 @@ private Font italic() {
 
  Font dialogFont = JFaceResources.getDialogFont();
  FontData[] fontData = dialogFont.getFontData();
- for (int i = 0; i < fontData.length; i++) {
- FontData data = fontData[i];
+ for (final FontData data : fontData) {
  data.setStyle(SWT.ITALIC);
  }
  Display display = getDisplay();

org.eclipse.lsp4e.debug/src/org/eclipse/lsp4e/debug/sourcelookup/AbsolutePathSourceContainer.java

@@ -8,6 +8,8 @@
  *******************************************************************************/
 package org.eclipse.lsp4e.debug.sourcelookup;
 
+import static org.eclipse.lsp4e.internal.ArrayUtil.NO_OBJECTS;
+
 import java.nio.file.Paths;
 
 import org.eclipse.core.runtime.CoreException;
@@ -23,7 +25,7 @@ public Object[] findSourceElements(String name) throws CoreException {
  if (name != null && Paths.get(name).isAbsolute()) {
  return new Object[] { name };
  }
- return new Object[0];
+ return NO_OBJECTS;
  }
 
  @Override

org.eclipse.lsp4e.jdt/src/org/eclipse/lsp4e/jdt/LSJavaCompletionProposalComputer.java

@@ -11,7 +11,6 @@
  *******************************************************************************/
 package org.eclipse.lsp4e.jdt;
 
-import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.CompletableFuture;
@@ -52,7 +51,7 @@ public List<ICompletionProposal> computeCompletionProposals(ContentAssistInvocat
  lsContentAssistProcessor.computeCompletionProposals(context.getViewer(), context.getInvocationOffset()));
 
  try {
- return Arrays.asList(asJavaProposals(future));
+ return List.of(asJavaProposals(future));
  } catch (ExecutionException | TimeoutException e) {
  LanguageServerPlugin.logError(e);
  javaCompletionSpecificErrorMessage = createErrorMessage(e);

org.eclipse.lsp4e.jdt/src/org/eclipse/lsp4e/jdt/LspJavaQuickAssistProcessor.java

@@ -30,6 +30,7 @@
 public class LspJavaQuickAssistProcessor extends LSPCodeActionQuickAssistProcessor implements IQuickAssistProcessor {
 
  private static final int RELEVANCE = 100;
+ private static final IJavaCompletionProposal[] NO_JAVA_COMPLETION_PROPOSALS = new IJavaCompletionProposal[0];
 
  private IQuickAssistInvocationContext getContext(IInvocationContext context) {
  return new IQuickAssistInvocationContext() {
@@ -63,7 +64,7 @@ public boolean hasAssists(@NonNullByDefault({}) IInvocationContext context) thro
 
  ICompletionProposal[] proposals = computeQuickAssistProposals(getContext(context));
  if (proposals == null)
- return new IJavaCompletionProposal[0];
+ return NO_JAVA_COMPLETION_PROPOSALS;
 
  final var javaProposals = new IJavaCompletionProposal[proposals.length];
  for (int i = 0; i < proposals.length; i++) {

org.eclipse.lsp4e.test/src/org/eclipse/lsp4e/test/edit/LSPEclipseUtilsTest.java

@@ -26,7 +26,6 @@
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
-import java.util.Arrays;
 import java.util.Collections;
 import java.util.LinkedList;
 import java.util.List;
@@ -272,7 +271,7 @@ public void testTextEditInsertSameOffset() throws Exception {
  new TextEdit(new Range(new Position(0, 0), new Position(0, 0)), " throws "),
  new TextEdit(new Range(new Position(0, 0), new Position(0, 0)), "Exception") };
  IDocument document = viewer.getDocument();
- LSPEclipseUtils.applyEdits(document, Arrays.asList(edits));
+ LSPEclipseUtils.applyEdits(document, List.of(edits));
  Assert.assertEquals(" throws Exception", document.get());
  }
 
@@ -285,7 +284,7 @@ public void testTextEditSplittedLineEndings() throws Exception {
  IDocument document = viewer.getDocument();
  int linesBeforeApplyEdits = document.getNumberOfLines();
  // WHEN the TextEdit gets applied to the document:
- LSPEclipseUtils.applyEdits(document, Arrays.asList(edits));
+ LSPEclipseUtils.applyEdits(document, List.of(edits));
  // THEN line1 has been swapped with line 3:
  Assert.assertEquals("line3\r\nline2\r\nline1\r\n", document.get());
  // AND the number of lines is still the same, because we have not appended a line:

org.eclipse.lsp4e.test/src/org/eclipse/lsp4e/test/operations/inlayhint/LSPLineContentCodeMiningTest.java

@@ -14,7 +14,6 @@
 
 import static org.junit.Assert.assertEquals;
 
-import java.util.Arrays;
 import java.util.List;
 import java.util.concurrent.TimeUnit;
 
@@ -86,7 +85,7 @@ private static InlayHintLabelPart createInlayLabelPart(String text, String comma
 
  private static InlayHint createMultiLabelInlayHint(InlayHintLabelPart... parts) {
  final var inlay = new InlayHint();
- inlay.setLabel(Arrays.asList(parts));
+ inlay.setLabel(List.of(parts));
  inlay.setPosition(new Position(0, 0));
  return inlay;
  }

org.eclipse.lsp4e.test/src/org/eclipse/lsp4e/test/utils/CreateAndRegisterContentTypeLSPLaunchConfigMapping.java

@@ -15,9 +15,10 @@
 import java.io.IOException;
 import java.net.URLClassLoader;
 import java.util.Arrays;
-import java.util.Collections;
 import java.util.HashSet;
 import java.util.LinkedList;
+import java.util.List;
+import java.util.Set;
 import java.util.stream.Collectors;
 
 import org.eclipse.core.externaltools.internal.IExternalToolConstants;
@@ -76,7 +77,7 @@ public void earlyStartup() {
  mockServerLauch = workingCopy.doSave();
  registry.registerAssociation(contentTypeManager.getContentType("org.eclipse.lsp4e.test.content-type2"),
  LaunchConfigurationStreamProvider.findLaunchConfiguration(IExternalToolConstants.ID_PROGRAM_LAUNCH_CONFIGURATION_TYPE, mockServerLauch.getName()),
- Collections.singleton(ILaunchManager.RUN_MODE));
+ Set.of(ILaunchManager.RUN_MODE));
  }
  } catch (CoreException e) {
  LanguageServerPlugin.logError(e);
@@ -87,7 +88,7 @@ public void earlyStartup() {
  private String getClassPath(Class<?> clazz) {
  ClassLoader loader = clazz.getClassLoader();
  if (loader instanceof URLClassLoader urlClassLoader) {
- return Arrays.asList(urlClassLoader.getURLs()).stream().map(url -> url.getFile()).collect(Collectors.joining(System.getProperty("path.separator")));
+ return List.of(urlClassLoader.getURLs()).stream().map(url -> url.getFile()).collect(Collectors.joining(System.getProperty("path.separator")));
  }
  final var toProcess = new LinkedList<Bundle>();
  final var processed = new HashSet<Bundle>();