Improve lambda method discovery Fixes: #477 (#478)

* Improve lambda method discovery Fixes: #477

Author: gayanper

com.microsoft.java.debug.plugin/src/main/java/com/microsoft/java/debug/BindingUtils.java

@@ -12,10 +12,12 @@
 package com.microsoft.java.debug;
 
 import org.eclipse.jdt.core.dom.IMethodBinding;
+import org.eclipse.jdt.internal.debug.core.breakpoints.LambdaLocationLocatorHelper;
 
 /**
  * Utility methods around working with JDT Bindings.
  */
+@SuppressWarnings("restriction")
 public final class BindingUtils {
     private BindingUtils() {
 
@@ -48,31 +50,14 @@ public static String getMethodName(IMethodBinding binding, boolean fromKey) {
     }
 
     /**
-     * Returns the method signature of the method represented by the binding. Since
-     * this implementation use the {@link IMethodBinding#getKey()} to extract the
-     * signature from, the method name must be passed in.
+     * Returns the method signature of the method represented by the binding
+     * including the synthetic outer locals.
      *
      * @param binding the binding which the signature must be resolved for.
-     * @param name    the name of the method.
-     * @return the signature or null if the signature could not be resolved from the
-     *         key.
+     * @return the signature or null if the signature could not be resolved.
      */
-    public static String toSignature(IMethodBinding binding, String name) {
-        // use key for now until JDT core provides a public API for this.
-        // "Ljava/util/Arrays;.asList<T:Ljava/lang/Object;>([TT;)Ljava/util/List<TT;>;"
-        // "([Ljava/lang/String;)V|Ljava/lang/InterruptedException;"
-        String signatureString = binding.getKey();
-        if (signatureString != null) {
-            name = "." + name;
-            int index = signatureString.indexOf(name);
-            if (index > -1) {
-                int exceptionIndex = signatureString.indexOf("|", signatureString.lastIndexOf(")"));
-                if (exceptionIndex > -1) {
-                    return signatureString.substring(index + name.length(), exceptionIndex);
-                }
-                return signatureString.substring(index + name.length());
-            }
-        }
-        return null;
+    public static String toSignature(IMethodBinding binding) {
+        return LambdaLocationLocatorHelper.toMethodSignature(binding);
     }
+
 }

com.microsoft.java.debug.plugin/src/main/java/com/microsoft/java/debug/BreakpointLocationLocator.java

@@ -46,7 +46,7 @@ public String getMethodSignature() {
         if (this.methodBinding == null) {
             return null;
         }
-        return BindingUtils.toSignature(this.methodBinding, getMethodName());
+        return BindingUtils.toSignature(this.methodBinding);
     }
 
     /**

com.microsoft.java.debug.plugin/src/main/java/com/microsoft/java/debug/LambdaExpressionLocator.java

@@ -71,7 +71,7 @@ public String getMethodSignature() {
         if (!this.found) {
             return null;
         }
-        return BindingUtils.toSignature(this.lambdaMethodBinding, getMethodName());
+        return BindingUtils.toSignature(this.lambdaMethodBinding);
     }
 
     /**

com.microsoft.java.debug.plugin/src/main/java/com/microsoft/java/debug/plugin/internal/JdtSourceLookUpProvider.java

@@ -29,10 +29,12 @@
 import java.util.jar.Manifest;
 import java.util.logging.Level;
 import java.util.logging.Logger;
-import java.util.stream.Stream;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
+import org.eclipse.core.resources.IFile;
 import org.eclipse.core.resources.IResource;
+import org.eclipse.core.resources.ResourcesPlugin;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.URIUtil;
 import org.eclipse.debug.core.sourcelookup.ISourceContainer;
@@ -50,10 +52,10 @@
 import org.eclipse.jdt.core.dom.ASTParser;
 import org.eclipse.jdt.core.dom.ASTVisitor;
 import org.eclipse.jdt.core.dom.CompilationUnit;
-import org.eclipse.jdt.core.dom.LambdaExpression;
-import org.eclipse.jdt.core.manipulation.CoreASTProvider;
 import org.eclipse.jdt.core.dom.IMethodBinding;
 import org.eclipse.jdt.core.dom.ITypeBinding;
+import org.eclipse.jdt.core.dom.LambdaExpression;
+import org.eclipse.jdt.core.manipulation.CoreASTProvider;
 import org.eclipse.jdt.internal.core.JarPackageFragmentRoot;
 import org.eclipse.jdt.launching.IVMInstall;
 import org.eclipse.jdt.launching.JavaRuntime;
@@ -276,7 +278,13 @@ private CompilationUnit asCompilationUnit(String uri) {
              * setEnvironment(String [], String [], String [], boolean)
              * and a unit name setUnitName(String).
              */
-            parser.setEnvironment(new String[0], new String[0], null, true);
+            IFile resource = (IFile) JDTUtils.findResource(JDTUtils.toURI(uri),
+                    ResourcesPlugin.getWorkspace().getRoot()::findFilesForLocationURI);
+            if (resource != null && JdtUtils.isJavaProject(resource.getProject())) {
+                parser.setProject(JavaCore.create(resource.getProject()));
+            } else {
+                parser.setEnvironment(new String[0], new String[0], null, true);
+            }
             parser.setUnitName(Paths.get(filePath).getFileName().toString());
             /**
              * See the java doc for { @link ASTParser#setSource(char[]) },
@@ -492,7 +500,7 @@ public List<MethodInvocation> findMethodInvocations(String uri, int line) {
                 // Keep consistent with JDI since JDI uses binary class name
                 invocation.declaringTypeName = binding.getDeclaringClass().getBinaryName();
             }
-            invocation.methodGenericSignature = BindingUtils.toSignature(binding, BindingUtils.getMethodName(binding, true));
+            invocation.methodGenericSignature = BindingUtils.toSignature(binding);
             invocation.methodSignature = Signature.getTypeErasure(invocation.methodGenericSignature);
             int startOffset = astNode.getStartPosition();
             if (astNode instanceof org.eclipse.jdt.core.dom.MethodInvocation) {