test: add UVA solution test runner

Author: lzwjava

src/test/java/UvaTest.java

@@ -0,0 +1,97 @@
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.InputStream;
+import java.io.PrintStream;
+import java.lang.reflect.Method;
+import java.nio.file.*;
+import java.util.*;
+import java.util.stream.*;
+import org.junit.jupiter.api.Test;
+
+class UvaTestRunner {
+
+    // Standard input for all tests (customize per problem if needed)
+    private static final String TEST_INPUT = "5\n1 2 3 4 5\n";
+    private static final String EXPECTED_OUTPUT = "15\n";
+
+    @Test
+    void testAllUvaSolutions() throws Exception {
+        List<Class<?>> solutionClasses = discoverUvaSolutionClasses();
+        assertFalse(solutionClasses.isEmpty(), "No UVA solution classes found");
+
+        for (Class<?> clazz : solutionClasses) {
+            testSolutionClass(clazz);
+        }
+    }
+
+    private List<Class<?>> discoverUvaSolutionClasses() throws Exception {
+        String basePackage = "com.algorithm.solutions.uva";
+        Path classLocation = Paths.get("target/classes", basePackage.replace('.', '/'));
+
+        return Files.walk(classLocation)
+                .filter(p -> p.toString().endsWith("Main.class"))
+                .map(p -> toClassName(p, classLocation, basePackage))
+                .map(this::loadClass)
+                .filter(Objects::nonNull)
+                .filter(this::hasMainMethod)
+                .collect(Collectors.toList());
+    }
+
+    private String toClassName(Path path, Path basePath, String basePackage) {
+        return basePackage + "."
+                + basePath.relativize(path)
+                        .toString()
+                        .replace(".class", "")
+                        .replace(FileSystems.getDefault().getSeparator(), ".");
+    }
+
+    private Class<?> loadClass(String className) {
+        try {
+            return Class.forName(className);
+        } catch (ClassNotFoundException e) {
+            return null;
+        }
+    }
+
+    private boolean hasMainMethod(Class<?> clazz) {
+        try {
+            Method main = clazz.getMethod("main", String[].class);
+            return main != null;
+        } catch (NoSuchMethodException e) {
+            return false;
+        }
+    }
+
+    private void testSolutionClass(Class<?> clazz) {
+        String className = clazz.getSimpleName();
+        System.out.println("Testing: " + clazz.getName());
+
+        // Redirect I/O
+        InputStream originalIn = System.in;
+        PrintStream originalOut = System.out;
+
+        try {
+            System.setIn(new ByteArrayInputStream(TEST_INPUT.getBytes()));
+            ByteArrayOutputStream outContent = new ByteArrayOutputStream();
+            System.setOut(new PrintStream(outContent));
+
+            // Invoke main method
+            Method main = clazz.getMethod("main", String[].class);
+            main.invoke(null, (Object) new String[0]);
+
+            // Verify output
+            String actualOutput = outContent.toString();
+            assertTrue(
+                    actualOutput.contains(EXPECTED_OUTPUT),
+                    "Failed for " + className + "\nExpected: " + EXPECTED_OUTPUT + "\nActual: " + actualOutput);
+
+        } catch (Exception e) {
+            fail("Exception in " + className + ": " + e.getMessage());
+        } finally {
+            System.setIn(originalIn);
+            System.setOut(originalOut);
+        }
+    }
+}