feat(http): Add NotFoundException and MethodNotAllowedException

Author: thced

src/main/java/com/retailsvc/http/MethodNotAllowedException.java

@@ -0,0 +1,17 @@
+package com.retailsvc.http;
+
+import com.retailsvc.http.spec.HttpMethod;
+import java.util.Set;
+
+public final class MethodNotAllowedException extends RuntimeException {
+  private final Set<HttpMethod> allowed;
+
+  public MethodNotAllowedException(Set<HttpMethod> allowed) {
+    super("method not allowed; allowed=" + allowed);
+    this.allowed = Set.copyOf(allowed);
+  }
+
+  public Set<HttpMethod> allowed() {
+    return allowed;
+  }
+}

src/main/java/com/retailsvc/http/NotFoundException.java

@@ -0,0 +1,7 @@
+package com.retailsvc.http;
+
+public final class NotFoundException extends RuntimeException {
+  public NotFoundException(String message) {
+    super(message);
+  }
+}

src/test/java/com/retailsvc/http/HttpExceptionsTest.java

@@ -0,0 +1,22 @@
+package com.retailsvc.http;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.retailsvc.http.spec.HttpMethod;
+import java.util.Set;
+import org.junit.jupiter.api.Test;
+
+class HttpExceptionsTest {
+  @Test
+  void notFoundCarriesPath() {
+    NotFoundException e = new NotFoundException("GET /missing");
+    assertThat(e.getMessage()).isEqualTo("GET /missing");
+  }
+
+  @Test
+  void methodNotAllowedCarriesAllowedSet() {
+    MethodNotAllowedException e =
+        new MethodNotAllowedException(Set.of(HttpMethod.GET, HttpMethod.POST));
+    assertThat(e.allowed()).containsExactlyInAnyOrder(HttpMethod.GET, HttpMethod.POST);
+  }
+}