test: add test for HandlerInfoTest

Author: maxday

aws-lambda-java-runtime-interface-client/src/test/java/com/amazonaws/services/lambda/runtime/api/client/HandlerInfoTest.java

@@ -0,0 +1,132 @@
+/*
+Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package com.amazonaws.services.lambda.runtime.api.client;
+
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+class HandlerInfoTest {
+
+    @Test
+    void testConstructor() {
+        Class<?> testClass = String.class;
+        String methodName = "testMethod";
+        
+        HandlerInfo info = new HandlerInfo(testClass, methodName);
+        
+        assertNotNull(info);
+        assertEquals(testClass, info.clazz);
+        assertEquals(methodName, info.methodName);
+    }
+
+    @Test
+    void testFromStringWithoutMethod() throws Exception {
+        String handler = "java.lang.String";
+        HandlerInfo info = HandlerInfo.fromString(handler, ClassLoader.getSystemClassLoader());
+        
+        assertEquals(String.class, info.clazz);
+        assertNull(info.methodName);
+    }
+
+    @Test
+    void testFromStringWithMethod() throws Exception {
+        String handler = "java.lang.String::length";
+        HandlerInfo info = HandlerInfo.fromString(handler, ClassLoader.getSystemClassLoader());
+        
+        assertEquals(String.class, info.clazz);
+        assertEquals("length", info.methodName);
+    }
+
+    @Test
+    void testFromStringWithEmptyClass() {
+        String handler = "::method";
+        
+        assertThrows(HandlerInfo.InvalidHandlerException.class, () ->
+            HandlerInfo.fromString(handler, ClassLoader.getSystemClassLoader())
+        );
+    }
+
+    @Test
+    void testFromStringWithEmptyMethod() {
+        String handler = "java.lang.String::";
+        
+        assertThrows(HandlerInfo.InvalidHandlerException.class, () ->
+            HandlerInfo.fromString(handler, ClassLoader.getSystemClassLoader())
+        );
+    }
+
+    @Test
+    void testFromStringWithNonexistentClass() {
+        String handler = "com.nonexistent.TestClass::method";
+        
+        assertThrows(ClassNotFoundException.class, () ->
+            HandlerInfo.fromString(handler, ClassLoader.getSystemClassLoader())
+        );
+    }
+
+    @Test
+    void testFromStringWithNullHandler() {
+        assertThrows(NullPointerException.class, () ->
+            HandlerInfo.fromString(null, ClassLoader.getSystemClassLoader())
+        );
+    }
+
+    @Test
+    void testClassNameWithoutMethod() {
+        String handler = "java.lang.String";
+        String className = HandlerInfo.className(handler);
+        
+        assertEquals("java.lang.String", className);
+    }
+
+    @Test
+    void testClassNameWithMethod() {
+        String handler = "java.lang.String::length";
+        String className = HandlerInfo.className(handler);
+        
+        assertEquals("java.lang.String", className);
+    }
+
+    @Test
+    void testClassNameWithEmptyString() {
+        String handler = "";
+        String className = HandlerInfo.className(handler);
+        
+        assertEquals("", className);
+    }
+
+    @Test
+    void testClassNameWithOnlyDelimiter() {
+        String handler = "::";
+        String className = HandlerInfo.className(handler);
+        
+        assertEquals("", className);
+    }
+
+    @Test
+    void testInvalidHandlerExceptionSerialVersionUID() {
+        assertEquals(-1L, HandlerInfo.InvalidHandlerException.serialVersionUID);
+    }
+
+    @Test
+    void testFromStringWithInnerClass() throws Exception {
+        // Create a custom class loader that can load our test class
+        ClassLoader cl = new ClassLoader() {
+            @Override
+            public Class<?> loadClass(String name) throws ClassNotFoundException {
+                if (name.equals("com.test.OuterClass$InnerClass")) {
+                    throw new ClassNotFoundException("Test class not found");
+                }
+                return super.loadClass(name);
+            }
+        };
+
+        String handler = "com.test.OuterClass$InnerClass::method";
+        assertThrows(ClassNotFoundException.class, () ->
+            HandlerInfo.fromString(handler, cl)
+        );
+    }
+}