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diff --git a/lib/java/test/org/apache/thrift/partial/ExceptionAsserts.java b/lib/java/test/org/apache/thrift/partial/ExceptionAsserts.java
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+++ b/lib/java/test/org/apache/thrift/partial/ExceptionAsserts.java
@@ -0,0 +1,92 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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 org.apache.thrift.partial;
+
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+public final class ExceptionAsserts {
+  private ExceptionAsserts() {}
+
+  @FunctionalInterface
+  public interface CodeThatMayThrow {
+    void run() throws Exception;
+  }
+
+  /**
+   * Asserts that the given code throws an exception of the given type
+   * and that the exception message contains the given sub-message.
+   *
+   * Usage:
+   *
+   * ExceptionAsserts.assertThrows(
+   *   IllegalArgumentException.class,
+   *   "'nullArg' must not be null",
+   *   () -> Preconditions.checkNotNull(null, "nullArg"));
+   *
+   * Note: JUnit 5 has similar functionality but it will be a long time before
+   * we move to that framework because of significant differences and lack of
+   * backward compatibility for some JUnit rules.
+   */
+  public static <E extends Exception> void assertThrows(
+      Class<E> expectedExceptionClass,
+      String partialMessage,
+      CodeThatMayThrow code) {
+
+    Exception thrownException = null;
+
+    try {
+      code.run();
+    } catch (Exception e) {
+      if (expectedExceptionClass.isAssignableFrom(e.getClass())) {
+
+        thrownException = e;
+
+        if (partialMessage != null) {
+          String msg = e.getMessage();
+          assertNotNull(
+              String.format("Exception message is null, expected to contain: '%s'", partialMessage),
+              msg);
+          assertTrue(
+              String.format("Exception message '%s' does not contain: '%s'", msg, partialMessage),
+              msg.contains(partialMessage));
+        }
+      } else {
+        fail(String.format(
+                 "Expected exception of type %s but got %s",
+                 expectedExceptionClass.getName(),
+                 e.getClass().getName()));
+      }
+    }
+
+    if (thrownException == null) {
+      fail(String.format(
+               "Expected exception of type %s but got none",
+               expectedExceptionClass.getName()));
+    }
+  }
+
+  public static <E extends Exception> void assertThrows(
+      Class<E> expectedExceptionClass,
+      CodeThatMayThrow code) {
+    assertThrows(expectedExceptionClass, null, code);
+  }
+}