Support intersection type casts

rewrite-java-11/src/main/java/org/openrewrite/java/isolated/ReloadableJava11ParserVisitor.java

@@ -721,6 +721,14 @@ public J visitInstanceOf(InstanceOfTree node, Space fmt) {
                 typeMapping.type(node));
     }
 
+    @Override
+    public J visitIntersectionType(IntersectionTypeTree node, Space fmt) {
+        JContainer<TypeTree> bounds = node.getBounds().isEmpty() ? null :
+                JContainer.build(EMPTY,
+                        convertAll(node.getBounds(), t -> sourceBefore("&"), noDelim), Markers.EMPTY);
+        return new J.IntersectionType(randomId(), fmt, Markers.EMPTY, bounds);
+    }
+
     @Override
     public J visitLabeledStatement(LabeledStatementTree node, Space fmt) {
         skip(node.getLabel().toString());

rewrite-java-11/src/main/java/org/openrewrite/java/isolated/ReloadableJava11TypeMapping.java

@@ -27,6 +27,7 @@
 import org.openrewrite.java.tree.TypeUtils;
 
 import javax.lang.model.type.NullType;
+import javax.lang.model.type.TypeMirror;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.util.ArrayList;
@@ -59,7 +60,9 @@ public JavaType type(@Nullable com.sun.tools.javac.code.Type type) {
             return existing;
         }
 
-        if (type instanceof Type.ClassType) {
+        if (type instanceof Type.IntersectionClassType) {
+            return intersectionType((Type.IntersectionClassType) type, signature);
+        } else if (type instanceof Type.ClassType) {
             return classType((Type.ClassType) type, signature);
         } else if (type instanceof Type.TypeVar) {
             return generic((Type.TypeVar) type, signature);
@@ -78,6 +81,19 @@ public JavaType type(@Nullable com.sun.tools.javac.code.Type type) {
         throw new UnsupportedOperationException("Unknown type " + type.getClass().getName());
     }
 
+    private JavaType intersectionType(Type.IntersectionClassType type, String signature) {
+        JavaType.Intersection intersection = new JavaType.Intersection(null);
+        typeCache.put(signature, intersection);
+        JavaType[] types = new JavaType[type.getBounds().size()];
+        List<? extends TypeMirror> bounds = type.getBounds();
+        for (int i = 0; i < bounds.size(); i++) {
+            TypeMirror bound = bounds.get(i);
+            types[i] = type((Type) bound);
+        }
+        intersection.unsafeSet(types);
+        return intersection;
+    }
+
     private JavaType array(Type type, String signature) {
         JavaType.Array arr = new JavaType.Array(null, null);
         typeCache.put(signature, arr);

rewrite-java-11/src/main/java/org/openrewrite/java/isolated/ReloadableJava11TypeSignatureBuilder.java

@@ -23,6 +23,7 @@
 import org.openrewrite.java.tree.JavaType;
 
 import javax.lang.model.type.NullType;
+import javax.lang.model.type.TypeMirror;
 import java.util.HashSet;
 import java.util.Set;
 import java.util.StringJoiner;
@@ -39,6 +40,13 @@ public String signature(@Nullable Object t) {
     private String signature(@Nullable Type type) {
         if (type == null || type instanceof Type.UnknownType || type instanceof NullType) {
             return "{undefined}";
+        } else if (type instanceof Type.IntersectionClassType) {
+            Type.IntersectionClassType intersectionClassType = (Type.IntersectionClassType) type;
+            StringJoiner joiner = new StringJoiner(" & ");
+            for (TypeMirror typeArg : intersectionClassType.getBounds()) {
+                joiner.add(signature(typeArg));
+            }
+            return joiner.toString();
         } else if (type instanceof Type.ClassType) {
             try {
                 return ((Type.ClassType) type).typarams_field != null && ((Type.ClassType) type).typarams_field.length() > 0 ? parameterizedSignature(type) : classSignature(type);

rewrite-java-17/src/main/java/org/openrewrite/java/isolated/ReloadableJava17ParserVisitor.java

@@ -780,6 +780,14 @@ public J visitInstanceOf(InstanceOfTree node, Space fmt) {
                 type);
     }
 
+    @Override
+    public J visitIntersectionType(IntersectionTypeTree node, Space fmt) {
+        JContainer<TypeTree> bounds = node.getBounds().isEmpty() ? null :
+                JContainer.build(EMPTY,
+                        convertAll(node.getBounds(), t -> sourceBefore("&"), noDelim), Markers.EMPTY);
+        return new J.IntersectionType(randomId(), fmt, Markers.EMPTY, bounds);
+    }
+
     @Override
     public J visitLabeledStatement(LabeledStatementTree node, Space fmt) {
         skip(node.getLabel().toString());

rewrite-java-17/src/main/java/org/openrewrite/java/isolated/ReloadableJava17TypeMapping.java

@@ -27,6 +27,7 @@
 import org.openrewrite.java.tree.TypeUtils;
 
 import javax.lang.model.type.NullType;
+import javax.lang.model.type.TypeMirror;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.util.ArrayList;
@@ -56,7 +57,9 @@ public JavaType type(@Nullable com.sun.tools.javac.code.Type type) {
             return existing;
         }
 
-        if (type instanceof Type.ClassType) {
+        if (type instanceof Type.IntersectionClassType) {
+            return intersectionType((Type.IntersectionClassType) type, signature);
+        } else if (type instanceof Type.ClassType) {
             return classType((Type.ClassType) type, signature);
         } else if (type instanceof Type.TypeVar) {
             return generic((Type.TypeVar) type, signature);
@@ -75,6 +78,19 @@ public JavaType type(@Nullable com.sun.tools.javac.code.Type type) {
         throw new UnsupportedOperationException("Unknown type " + type.getClass().getName());
     }
 
+    private JavaType intersectionType(Type.IntersectionClassType type, String signature) {
+        JavaType.Intersection intersection = new JavaType.Intersection(null);
+        typeCache.put(signature, intersection);
+        JavaType[] types = new JavaType[type.getBounds().size()];
+        List<? extends TypeMirror> bounds = type.getBounds();
+        for (int i = 0; i < bounds.size(); i++) {
+            TypeMirror bound = bounds.get(i);
+            types[i] = type((Type) bound);
+        }
+        intersection.unsafeSet(types);
+        return intersection;
+    }
+
     private JavaType array(Type type, String signature) {
         JavaType.Array arr = new JavaType.Array(null, null);
         typeCache.put(signature, arr);

rewrite-java-17/src/main/java/org/openrewrite/java/isolated/ReloadableJava17TypeSignatureBuilder.java

@@ -23,6 +23,7 @@
 import org.openrewrite.java.tree.JavaType;
 
 import javax.lang.model.type.NullType;
+import javax.lang.model.type.TypeMirror;
 import java.util.HashSet;
 import java.util.Set;
 import java.util.StringJoiner;
@@ -39,6 +40,13 @@ public String signature(@Nullable Object t) {
     private String signature(@Nullable Type type) {
         if (type == null || type instanceof Type.UnknownType || type instanceof NullType) {
             return "{undefined}";
+        } else if (type instanceof Type.IntersectionClassType) {
+            Type.IntersectionClassType intersectionClassType = (Type.IntersectionClassType) type;
+            StringJoiner joiner = new StringJoiner(" & ");
+            for (TypeMirror typeArg : intersectionClassType.getBounds()) {
+                joiner.add(signature(typeArg));
+            }
+            return joiner.toString();
         } else if (type instanceof Type.ClassType) {
             try {
                 return ((Type.ClassType) type).typarams_field != null && ((Type.ClassType) type).typarams_field.length() > 0 ? parameterizedSignature(type) : classSignature(type);

rewrite-java-21/src/main/java/org/openrewrite/java/isolated/ReloadableJava21ParserVisitor.java

@@ -780,6 +780,14 @@ public J visitInstanceOf(InstanceOfTree node, Space fmt) {
                 type);
     }
 
+    @Override
+    public J visitIntersectionType(IntersectionTypeTree node, Space fmt) {
+        JContainer<TypeTree> bounds = node.getBounds().isEmpty() ? null :
+                JContainer.build(EMPTY,
+                        convertAll(node.getBounds(), t -> sourceBefore("&"), noDelim), Markers.EMPTY);
+        return new J.IntersectionType(randomId(), fmt, Markers.EMPTY, bounds);
+    }
+
     @Override
     public J visitLabeledStatement(LabeledStatementTree node, Space fmt) {
         skip(node.getLabel().toString());

rewrite-java-21/src/main/java/org/openrewrite/java/isolated/ReloadableJava21TypeMapping.java

@@ -27,6 +27,7 @@
 import org.openrewrite.java.tree.TypeUtils;
 
 import javax.lang.model.type.NullType;
+import javax.lang.model.type.TypeMirror;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.util.ArrayList;
@@ -56,7 +57,9 @@ public JavaType type(@Nullable com.sun.tools.javac.code.Type type) {
             return existing;
         }
 
-        if (type instanceof Type.ClassType) {
+        if (type instanceof Type.IntersectionClassType) {
+            return intersectionType((Type.IntersectionClassType) type, signature);
+        } else if (type instanceof Type.ClassType) {
             return classType((Type.ClassType) type, signature);
         } else if (type instanceof Type.TypeVar) {
             return generic((Type.TypeVar) type, signature);
@@ -75,6 +78,19 @@ public JavaType type(@Nullable com.sun.tools.javac.code.Type type) {
         throw new UnsupportedOperationException("Unknown type " + type.getClass().getName());
     }
 
+    private JavaType intersectionType(Type.IntersectionClassType type, String signature) {
+        JavaType.Intersection intersection = new JavaType.Intersection(null);
+        typeCache.put(signature, intersection);
+        JavaType[] types = new JavaType[type.getBounds().size()];
+        List<? extends TypeMirror> bounds = type.getBounds();
+        for (int i = 0; i < bounds.size(); i++) {
+            TypeMirror bound = bounds.get(i);
+            types[i] = type((Type) bound);
+        }
+        intersection.unsafeSet(types);
+        return intersection;
+    }
+
     private JavaType array(Type type, String signature) {
         JavaType.Array arr = new JavaType.Array(null, null);
         typeCache.put(signature, arr);

rewrite-java-21/src/main/java/org/openrewrite/java/isolated/ReloadableJava21TypeSignatureBuilder.java

@@ -23,6 +23,7 @@
 import org.openrewrite.java.tree.JavaType;
 
 import javax.lang.model.type.NullType;
+import javax.lang.model.type.TypeMirror;
 import java.util.HashSet;
 import java.util.Set;
 import java.util.StringJoiner;
@@ -39,6 +40,13 @@ public String signature(@Nullable Object t) {
     private String signature(@Nullable Type type) {
         if (type == null || type instanceof Type.UnknownType || type instanceof NullType) {
             return "{undefined}";
+        } else if (type instanceof Type.IntersectionClassType) {
+            Type.IntersectionClassType intersectionClassType = (Type.IntersectionClassType) type;
+            StringJoiner joiner = new StringJoiner(" & ");
+            for (TypeMirror typeArg : intersectionClassType.getBounds()) {
+                joiner.add(signature(typeArg));
+            }
+            return joiner.toString();
         } else if (type instanceof Type.ClassType) {
             try {
                 return ((Type.ClassType) type).typarams_field != null && ((Type.ClassType) type).typarams_field.length() > 0 ? parameterizedSignature(type) : classSignature(type);

rewrite-java-8/src/main/java/org/openrewrite/java/ReloadableJava8ParserVisitor.java

@@ -719,6 +719,14 @@ public J visitInstanceOf(InstanceOfTree node, Space fmt) {
                 typeMapping.type(node));
     }
 
+    @Override
+    public J visitIntersectionType(IntersectionTypeTree node, Space fmt) {
+        JContainer<TypeTree> bounds = node.getBounds().isEmpty() ? null :
+                JContainer.build(EMPTY,
+                        convertAll(node.getBounds(), t -> sourceBefore("&"), noDelim), Markers.EMPTY);
+        return new J.IntersectionType(randomId(), fmt, Markers.EMPTY, bounds);
+    }
+
     @Override
     public J visitLabeledStatement(LabeledStatementTree node, Space fmt) {
         skip(node.getLabel().toString());

rewrite-java-8/src/main/java/org/openrewrite/java/ReloadableJava8TypeMapping.java

@@ -26,6 +26,7 @@
 import org.openrewrite.java.tree.TypeUtils;
 
 import javax.lang.model.type.NullType;
+import javax.lang.model.type.TypeMirror;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.util.ArrayList;
@@ -58,7 +59,9 @@ public JavaType type(@Nullable com.sun.tools.javac.code.Type type) {
             return existing;
         }
 
-        if (type instanceof Type.ClassType) {
+        if (type instanceof Type.IntersectionClassType) {
+            return intersectionType((Type.IntersectionClassType) type, signature);
+        } else if (type instanceof Type.ClassType) {
             return classType((Type.ClassType) type, signature);
         } else if (type instanceof Type.TypeVar) {
             return generic((Type.TypeVar) type, signature);
@@ -79,6 +82,19 @@ public JavaType type(@Nullable com.sun.tools.javac.code.Type type) {
         throw new UnsupportedOperationException("Unknown type " + type.getClass().getName());
     }
 
+    private JavaType intersectionType(Type.IntersectionClassType type, String signature) {
+        JavaType.Intersection intersection = new JavaType.Intersection(null);
+        typeCache.put(signature, intersection);
+        JavaType[] types = new JavaType[type.getBounds().size()];
+        List<? extends TypeMirror> bounds = type.getBounds();
+        for (int i = 0; i < bounds.size(); i++) {
+            TypeMirror bound = bounds.get(i);
+            types[i] = type((Type) bound);
+        }
+        intersection.unsafeSet(types);
+        return intersection;
+    }
+
     private JavaType array(Type type, String signature) {
         JavaType.Array arr = new JavaType.Array(null, null);
         typeCache.put(signature, arr);

rewrite-java-8/src/main/java/org/openrewrite/java/ReloadableJava8TypeSignatureBuilder.java

@@ -22,6 +22,7 @@
 import org.openrewrite.java.tree.JavaType;
 
 import javax.lang.model.type.NullType;
+import javax.lang.model.type.TypeMirror;
 import java.util.HashSet;
 import java.util.Set;
 import java.util.StringJoiner;
@@ -38,6 +39,13 @@ public String signature(@Nullable Object t) {
     private String signature(@Nullable Type type) {
         if (type == null || type instanceof Type.UnknownType || type instanceof NullType) {
             return "{undefined}";
+        } else if (type instanceof Type.IntersectionClassType) {
+            Type.IntersectionClassType intersectionClassType = (Type.IntersectionClassType) type;
+            StringJoiner joiner = new StringJoiner(" & ");
+            for (TypeMirror typeArg : intersectionClassType.getBounds()) {
+                joiner.add(signature(typeArg));
+            }
+            return joiner.toString();
         } else if (type instanceof Type.ClassType) {
             try {
                 return ((Type.ClassType) type).typarams_field != null && ((Type.ClassType) type).typarams_field.length() > 0 ? parameterizedSignature(type) : classSignature(type);

rewrite-java-tck/src/main/java/org/openrewrite/java/tree/TypeCastTest.java

@@ -16,8 +16,10 @@
 package org.openrewrite.java.tree;
 
 import org.junit.jupiter.api.Test;
+import org.openrewrite.java.MinimumJava11;
 import org.openrewrite.test.RewriteTest;
 
+import static org.assertj.core.api.Assertions.assertThat;
 import static org.openrewrite.java.Assertions.java;
 
 class TypeCastTest implements RewriteTest {
@@ -35,4 +37,59 @@ class Test {
           )
         );
     }
+
+    @Test
+    void intersectionCast() {
+        rewriteRun(
+          java(
+            """
+              import java.io.Serializable;
+              import java.util.function.BiFunction;
+
+              class Test {
+                  Serializable s = (Serializable & BiFunction<Integer, Integer, Integer>) Integer::sum;
+              }
+              """
+          )
+        );
+    }
+
+    @MinimumJava11
+    @Test
+    void intersectionCastAssignedToVar() {
+        rewriteRun(
+          java(
+            """
+              import java.io.Serializable;
+              import java.util.function.BiFunction;
+
+              class Test {
+                  void m() {
+                      var s = (Serializable & BiFunction<Integer, Integer, Integer>) Integer::sum;
+                  }
+              }
+              """,
+            spec -> spec.afterRecipe(cu -> {
+                J.MethodDeclaration m = (J.MethodDeclaration) cu.getClasses().get(0).getBody().getStatements().get(0);
+                J.VariableDeclarations s = (J.VariableDeclarations) m.getBody().getStatements().get(0);
+                assertThat(s.getType()).isInstanceOf(JavaType.Intersection.class);
+                JavaType.Intersection intersection = (JavaType.Intersection) s.getType();
+                assertThat(intersection.getBounds()).satisfiesExactly(
+                  b1 -> assertThat(b1).satisfies(
+                    t -> assertThat(t).isInstanceOf(JavaType.Class.class),
+                    t -> assertThat(((JavaType.Class) t).getFullyQualifiedName()).isEqualTo("java.io.Serializable")
+                  ),
+                  b2 -> assertThat(b2).satisfies(
+                    t -> assertThat(t).isInstanceOf(JavaType.Parameterized.class),
+                    t -> assertThat(((JavaType.Parameterized) t).getFullyQualifiedName()).isEqualTo("java.util.function.BiFunction"),
+                    t -> assertThat(((JavaType.Parameterized) t).getTypeParameters()).hasSize(3),
+                    t -> assertThat(((JavaType.Parameterized) t).getTypeParameters()).allSatisfy(
+                      p -> assertThat(((JavaType.Class) p).getFullyQualifiedName()).isEqualTo("java.lang.Integer")
+                    )
+                  )
+                );
+            })
+          )
+        );
+    }
 }