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diff --git a/java/dagger/hilt/processor/internal/MethodSignature.java b/java/dagger/hilt/processor/internal/MethodSignature.java
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+++ b/java/dagger/hilt/processor/internal/MethodSignature.java
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+/*
+ * Copyright (C) 2023 The Dagger Authors.
+ *
+ * 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 dagger.hilt.processor.internal;
+
+import static dagger.internal.codegen.extension.DaggerStreams.toImmutableList;
+import static java.util.stream.Collectors.joining;
+
+import androidx.room.compiler.processing.XExecutableElement;
+import androidx.room.compiler.processing.XMethodElement;
+import androidx.room.compiler.processing.XMethodType;
+import androidx.room.compiler.processing.XType;
+import com.google.auto.value.AutoValue;
+import com.google.common.collect.ImmutableList;
+import com.squareup.javapoet.MethodSpec;
+import com.squareup.javapoet.TypeName;
+import dagger.internal.codegen.xprocessing.XElements;
+
+/** Represents the method signature needed to uniquely identify a method. */
+@AutoValue
+public abstract class MethodSignature {
+  MethodSignature() {}
+
+  abstract String name();
+
+  abstract ImmutableList<TypeName> parameters();
+
+  /** Creates a {@link MethodSignature} from a method name and parameter {@link TypeNames} */
+  public static MethodSignature of(String methodName, TypeName... typeNames) {
+    return new AutoValue_MethodSignature(methodName, ImmutableList.copyOf(typeNames));
+  }
+
+  /** Creates a {@link MethodSignature} from a {@link MethodSpec} */
+  public static MethodSignature of(MethodSpec method) {
+    return new AutoValue_MethodSignature(
+        method.name, method.parameters.stream().map(p -> p.type).collect(toImmutableList()));
+  }
+
+  /** Creates a {@link MethodSignature} from an {@link XExecutableElement} */
+  public static MethodSignature of(XExecutableElement executableElement) {
+    return new AutoValue_MethodSignature(
+        XElements.getSimpleName(executableElement),
+        executableElement.getParameters().stream()
+            .map(p -> p.getType().getTypeName())
+            .collect(toImmutableList()));
+  }
+
+  /**
+   * Creates a {@link MethodSignature} from an {@link XMethodElement}.
+   *
+   * <p>This version will resolve type parameters as declared by {@code enclosing}.
+   */
+  static MethodSignature ofDeclaredType(XMethodElement method, XType enclosing) {
+    XMethodType executableType = method.asMemberOf(enclosing);
+    return new AutoValue_MethodSignature(
+        XElements.getSimpleName(method),
+        executableType.getParameterTypes().stream()
+            .map(XType::getTypeName)
+            .collect(toImmutableList()));
+  }
+
+  /** Returns a string in the format: METHOD_NAME(PARAM_TYPE1,PARAM_TYEP2,...) */
+  @Override
+  public final String toString() {
+    return String.format(
+        "%s(%s)", name(), parameters().stream().map(Object::toString).collect(joining(",")));
+  }
+}