1 files changed, 63 insertions, 0 deletions
diff --git a/src/main/java/com/code_intelligence/jazzer/mutation/support/ParameterHolder.java b/src/main/java/com/code_intelligence/jazzer/mutation/support/ParameterHolder.java
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+/*
+ * Copyright 2023 Code Intelligence GmbH
+ *
+ * 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.code_intelligence.jazzer.mutation.support;
+
+import static com.code_intelligence.jazzer.mutation.support.Preconditions.require;
+import static java.util.stream.Collectors.toList;
+
+import java.lang.annotation.Annotation;
+import java.lang.reflect.AnnotatedType;
+import java.lang.reflect.Method;
+import java.lang.reflect.Type;
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * A factory for {@link AnnotatedType} instances capturing method parameters.
+ *
+ * <p>Due to type erasure, this class can only be used by creating an anonymous subclass with a
+ * method called {@code foo} that takes exactly the desired parameter.
+ *
+ * <p>Example: {@code new ParameterHolder {void foo(@NotNull List<String> param)}.annotatedType}
+ */
+public abstract class ParameterHolder {
+  protected ParameterHolder() {}
+
+  public AnnotatedType annotatedType() {
+    return getMethod().getAnnotatedParameterTypes()[0];
+  }
+
+  public Type type() {
+    return annotatedType().getType();
+  }
+
+  public Annotation[] parameterAnnotations() {
+    return getMethod().getParameterAnnotations()[0];
+  }
+
+  private Method getMethod() {
+    List<Method> foos = Arrays.stream(this.getClass().getDeclaredMethods())
+                            .filter(method -> method.getName().equals("foo"))
+                            .collect(toList());
+    require(foos.size() == 1,
+        this.getClass().getName() + " must define exactly one function named 'foo'");
+    Method foo = foos.get(0);
+    require(foo.getParameterCount() == 1,
+        this.getClass().getName() + "#foo must define exactly one parameter");
+    return foo;
+  }
+}