Add expectException to policy-common

Also fixed new checkstyle error.

Change-Id: I2d2c2518f3f7da1a0ace8c32e10b4151d941bb6f
Issue-ID: POLICY-1148
Signed-off-by: Jim Hahn <jrh3@att.com>

2 files changed, 128 insertions, 0 deletions

diff --git a/utils-test/src/main/java/org/onap/policy/common/utils/test/PolicyAssert.java b/utils-test/src/main/java/org/onap/policy/common/utils/test/PolicyAssert.java
new file mode 100644
index 00000000..fdd098f6
--- /dev/null
+++ b/utils-test/src/main/java/org/onap/policy/common/utils/test/PolicyAssert.java
@@ -0,0 +1,61 @@
+/*
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2018 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.utils.test;
+
+public class PolicyAssert {
+
+    /**
+     * Should not instantiate this.
+     */
+    private PolicyAssert() {
+        // do nothing
+    }
+
+    /**
+     * Invokes a function that is expected to throw an exception.
+     *
+     * @param clazz class of exception that is expected
+     * @param func function
+     * @return object
+     */
+    public static <T> T assertException(Class<T> clazz, RunnableWithEx func) {
+        try {
+            func.run();
+            throw new AssertionError("missing exception");
+
+        } catch (Exception e) {
+            try {
+                return clazz.cast(e);
+
+            } catch (ClassCastException e2) {
+                throw new AssertionError("incorrect exception type", e2);
+            }
+        }
+    }
+
+    /**
+     * Runnable that may throw an exception.
+     */
+    @FunctionalInterface
+    public static interface RunnableWithEx {
+        public void run() throws Exception;
+    }
+}
diff --git a/utils-test/src/test/java/org/onap/policy/common/utils/test/PolicyAssertTest.java b/utils-test/src/test/java/org/onap/policy/common/utils/test/PolicyAssertTest.java
new file mode 100644
index 00000000..2831905c
--- /dev/null
+++ b/utils-test/src/test/java/org/onap/policy/common/utils/test/PolicyAssertTest.java
@@ -0,0 +1,67 @@
+/*
+ * ============LICENSE_START=======================================================
+ * Common Utils-Test
+ * ================================================================================
+ * Copyright (C) 2018 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.utils.test;
+
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import static org.onap.policy.common.utils.test.PolicyAssert.assertException;
+
+import org.junit.Test;
+
+public class PolicyAssertTest {
+
+    private static final String EXPECTED = "expected exception";
+
+    @Test
+    public void test_ExpectedEx() {
+        assertException(IllegalArgumentException.class, () -> {
+            throw new IllegalArgumentException(EXPECTED);
+        });
+    }
+
+    @Test
+    public void test_IncorrectEx() {
+        try {
+            assertException(IllegalStateException.class, () -> {
+                throw new IllegalArgumentException(EXPECTED);
+            });
+
+            fail("incorrect exception type");
+
+        } catch (AssertionError err) {
+            assertTrue(err.getMessage().contains("incorrect exception type"));
+        }
+    }
+
+    @Test
+    public void test_MissingEx() {
+        try {
+            assertException(IllegalArgumentException.class, () -> {
+            });
+
+            fail("missing exception");
+
+        } catch (AssertionError err) {
+            assertTrue(err.getMessage().contains("missing exception"));
+        }
+    }
+
+}