Lambda expressions support: first round

java/java-psi-api/src/com/intellij/psi/JavaElementVisitor.java

@@ -375,4 +375,8 @@ public abstract class JavaElementVisitor extends PsiElementVisitor {
   public void visitPolyadicExpression(PsiPolyadicExpression expression) {
     visitExpression(expression);
   }
+
+  public void visitLambdaExpression(PsiLambdaExpression expression) {
+    visitExpression(expression);
+  }
 }

java/java-psi-api/src/com/intellij/psi/PsiLambdaExpression.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2000-2012 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.psi;
+
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * Represents a Java lambda expression.
+ */
+public interface PsiLambdaExpression extends PsiExpression {
+  /**
+   * Returns this lambda expression's parameter list.
+   *
+   * @return parameter list.
+   */
+  @NotNull
+  PsiParameterList getParameterList();
+
+  /**
+   * Returns PSI element representing lambda expression body: {@link PsiCodeBlock}, {@link PsiExpression}, or null if none.
+   *
+   * @return lambda expression body.
+   */
+  @Nullable
+  PsiElement getBody();
+}

java/java-psi-api/src/com/intellij/psi/PsiLambdaExpressionType.java

@@ -0,0 +1,73 @@
+/*
+ * Copyright 2000-2012 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.psi;
+
+import com.intellij.psi.search.GlobalSearchScope;
+import org.jetbrains.annotations.NonNls;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * A type which represents a function denoted by a lambda expression.
+ */
+public class PsiLambdaExpressionType extends PsiType {
+  private final PsiLambdaExpression myExpression;
+
+  public PsiLambdaExpressionType(PsiLambdaExpression expression) {
+    super(PsiAnnotation.EMPTY_ARRAY);
+    myExpression = expression;
+  }
+
+  @Override
+  public String getPresentableText() {
+    return "<lambda expression>";
+  }
+
+  @Override
+  public String getCanonicalText() {
+    return getPresentableText();
+  }
+
+  @Override
+  public String getInternalCanonicalText() {
+    return getCanonicalText();
+  }
+
+  @Override
+  public boolean isValid() {
+    return myExpression.isValid();
+  }
+
+  @Override
+  public boolean equalsToText(@NonNls final String text) {
+    return false;
+  }
+
+  @Override
+  public <A> A accept(@NotNull final PsiTypeVisitor<A> visitor) {
+    return visitor.visitType(this);
+  }
+
+  @Override
+  public GlobalSearchScope getResolveScope() {
+    return null;
+  }
+
+  @NotNull
+  @Override
+  public PsiType[] getSuperTypes() {
+    return PsiType.EMPTY_ARRAY;
+  }
+}

java/java-psi-api/src/com/intellij/psi/PsiLambdaParameterType.java

@@ -0,0 +1,73 @@
+/*
+ * Copyright 2000-2012 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.psi;
+
+import com.intellij.psi.search.GlobalSearchScope;
+import org.jetbrains.annotations.NonNls;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * A type which represents an omitted type for parameter of lambda expression.
+ */
+public class PsiLambdaParameterType extends PsiType {
+  private final PsiParameter myParameter;
+
+  public PsiLambdaParameterType(PsiParameter parameter) {
+    super(PsiAnnotation.EMPTY_ARRAY);
+    myParameter = parameter;
+  }
+
+  @Override
+  public String getPresentableText() {
+    return "<lambda parameter>";
+  }
+
+  @Override
+  public String getCanonicalText() {
+    return getPresentableText();
+  }
+
+  @Override
+  public String getInternalCanonicalText() {
+    return getCanonicalText();
+  }
+
+  @Override
+  public boolean isValid() {
+    return myParameter.isValid();
+  }
+
+  @Override
+  public boolean equalsToText(@NonNls final String text) {
+    return false;
+  }
+
+  @Override
+  public <A> A accept(@NotNull final PsiTypeVisitor<A> visitor) {
+    return visitor.visitType(this);
+  }
+
+  @Override
+  public GlobalSearchScope getResolveScope() {
+    return null;
+  }
+
+  @NotNull
+  @Override
+  public PsiType[] getSuperTypes() {
+    return PsiType.EMPTY_ARRAY;
+  }
+}

java/java-psi-api/src/com/intellij/psi/PsiMethodReferenceType.java

@@ -57,7 +57,7 @@ public class PsiMethodReferenceType extends PsiType {
 
   @Override
   public <A> A accept(@NotNull final PsiTypeVisitor<A> visitor) {
-    return visitor.visitMethodReferenceType(this);
+    return visitor.visitType(this);
   }
 
   @Override

java/java-psi-api/src/com/intellij/psi/PsiTypeVisitor.java

@@ -56,8 +56,4 @@ public class PsiTypeVisitor<A> {
   public A visitDiamondType(PsiDiamondType diamondType) {
     return visitType(diamondType);
   }
-
-  public A visitMethodReferenceType(PsiMethodReferenceType methodReferenceType) {
-    return visitType(methodReferenceType);
-  }
 }

java/java-psi-api/src/com/intellij/psi/util/TypeConversionUtil.java

@@ -644,6 +644,7 @@ public class TypeConversionUtil {
 
     // todo[r.sh] implement
     if (right instanceof PsiMethodReferenceType && left instanceof PsiClassType) return true;
+    if (right instanceof PsiLambdaExpressionType && left instanceof PsiClassType) return true;
 
     if (left instanceof PsiIntersectionType) {
       PsiType[] conjuncts = ((PsiIntersectionType)left).getConjuncts();