test: add test for classpath

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

@@ -0,0 +1,125 @@
+/*
+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 org.junit.jupiter.api.io.TempDir;
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.nio.file.Path;
+import java.util.Collections;
+import java.util.Enumeration;
+import java.util.jar.JarEntry;
+import java.util.jar.JarFile;
+import java.util.jar.JarOutputStream;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class ClasspathLoaderTest {
+
+    @Test
+    void testLoadAllClassesWithNoClasspath() throws IOException {
+        String originalClasspath = System.getProperty("java.class.path");
+        try {
+            System.clearProperty("java.class.path");
+            ClasspathLoader.main(new String[]{});
+        } finally {
+            if (originalClasspath != null) {
+                System.setProperty("java.class.path", originalClasspath);
+            }
+        }
+    }
+
+    @Test
+    void testLoadAllClassesWithEmptyClasspath() {
+        String originalClasspath = System.getProperty("java.class.path");
+        try {
+            System.setProperty("java.class.path", "");
+            assertThrows(FileNotFoundException.class, () -> 
+                ClasspathLoader.main(new String[]{}));
+        } finally {
+            if (originalClasspath != null) {
+                System.setProperty("java.class.path", originalClasspath);
+            }
+        }
+    }
+
+    @Test
+    void testLoadAllClassesWithInvalidPath() {
+        String originalClasspath = System.getProperty("java.class.path");
+        try {
+            System.setProperty("java.class.path", "nonexistent/path");
+            assertThrows(FileNotFoundException.class, () -> 
+                ClasspathLoader.main(new String[]{}));
+        } finally {
+            if (originalClasspath != null) {
+                System.setProperty("java.class.path", originalClasspath);
+            }
+        }
+    }
+
+    @Test
+    void testLoadAllClassesWithValidJar(@TempDir Path tempDir) throws IOException {
+        File jarFile = createSimpleJar(tempDir, "test.jar", "TestClass");
+        String originalClasspath = System.getProperty("java.class.path");
+        try {
+            System.setProperty("java.class.path", jarFile.getAbsolutePath());
+            ClasspathLoader.main(new String[]{});
+        } finally {
+            if (originalClasspath != null) {
+                System.setProperty("java.class.path", originalClasspath);
+            }
+        }
+    }
+
+    @Test
+    void testLoadAllClassesWithDirectory(@TempDir Path tempDir) throws IOException {
+        String originalClasspath = System.getProperty("java.class.path");
+        try {
+            System.setProperty("java.class.path", tempDir.toString());
+            ClasspathLoader.main(new String[]{});
+        } finally {
+            if (originalClasspath != null) {
+                System.setProperty("java.class.path", originalClasspath);
+            }
+        }
+    }
+
+    @Test
+    void testLoadAllClassesWithMultipleEntries(@TempDir Path tempDir) throws IOException {
+        File jarFile1 = createSimpleJar(tempDir, "test1.jar", "TestClass1");
+        File jarFile2 = createSimpleJar(tempDir, "test2.jar", "TestClass2");
+
+        String originalClasspath = System.getProperty("java.class.path");
+        try {
+            String newClasspath = jarFile1.getAbsolutePath() + 
+                                File.pathSeparator + 
+                                jarFile2.getAbsolutePath();
+            System.setProperty("java.class.path", newClasspath);
+            ClasspathLoader.main(new String[]{});
+        } finally {
+            if (originalClasspath != null) {
+                System.setProperty("java.class.path", originalClasspath);
+            }
+        }
+    }
+
+    private File createSimpleJar(Path tempDir, String jarName, String className) throws IOException {
+        File jarFile = tempDir.resolve(jarName).toFile();
+
+        try (JarOutputStream jos = new JarOutputStream(new FileOutputStream(jarFile))) {
+            // Add a simple non-class file to make it a valid jar
+            JarEntry entry = new JarEntry("com/test/" + className + ".txt");
+            jos.putNextEntry(entry);
+            jos.write("test content".getBytes());
+            jos.closeEntry();
+        }
+
+        return jarFile;
+    }
+}

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

@@ -1,4 +1,7 @@
-/* Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. */
+/*
+Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+SPDX-License-Identifier: Apache-2.0
+*/
 
 package com.amazonaws.services.lambda.runtime.api.client;