<dependency>
    <groupId>com.sparkjava</groupId>
    <artifactId>spark-core</artifactId>
    <version>2.0.0</version>
</dependency>

import static spark.Spark.*;

    public class HelloWorld {
        public static void main(String[] args) {
            get("/hello", (req, res) -> "Hello World");
        }
    }

http://localhost:4567/hello

get("/", (request, response) -> {
// .. Show something ..
});

post("/", (request, response) -> {
// .. Create something ..
});

put("/", (request, response) -> {
// .. Update something ..
});

delete("/", (request, response) -> {
// .. annihilate something ..
});

options("/", (request, response) -> {
// .. appease something ..
});

// matches "GET /hello/foo" and "GET /hello/bar"
// request.params(":name") is 'foo' or 'bar'
get("/hello/:name", (request, response) -> {
    return "Hello: " + request.params(":name");
});

// matches "GET /say/hello/to/world"
// request.splat()[0] is 'hello' and request.splat()[1] 'world'
get("/say/*/to/*", (request, response) -> {
    return "Number of splat parameters: " + request.splat().length;
});

request.body();               // request body sent by the client
request.cookies();            // request cookies sent by the client
request.contentLength();      // length of request body
request.contentType();        // content type of request.body
request.headers();            // the HTTP header list
request.headers("BAR");       // value of BAR header
request.attributes();         // the attributes list
request.attribute("foo");     // value of foo attribute
request.attribute("A", "V");  // sets value of attribute A to V
request.host();               // "example.com"
request.ip();                 // client IP address
request.pathInfo();           // the path info
request.params("foo");        // value of foo path parameter
request.params();             // map with all parameters
request.port();               // the server port
request.queryMap();           // the query map
request.queryMap("foo");      // query map for a certain parameter
request.queryParams("FOO");   // value of FOO query param
request.queryParams();        // the query param list
request.raw();                // raw request handed in by Jetty
request.requestMethod();      // The HTTP method (GET, ..etc)
request.scheme();             // "http"
request.session();            // session management
request.splat();              // splat (*) parameters
request.url();                // "http://example.com/foo"
request.userAgent();          // user agent

response.body("Hello");        // sets content to Hello
response.header("FOO", "bar"); // sets header FOO with value bar
response.raw();                // raw response handed in by Jetty
response.redirect("/example"); // browser redirect to /example
response.status(401);          // set status code to 401
response.type("text/xml");     // set content type to text/xml

request.queryMap().get("user", "name").value();
request.queryMap().get("user").get("name").value();
request.queryMap("user").get("age").integerValue();
request.queryMap("user").toMap();

request.cookies();                              // get map of all request cookies
request.cookie("foo");                          // access request cookie by name
response.cookie("foo", "bar");                  // set cookie with a value
response.cookie("foo", "bar", 3600);            // set cookie with a max-age
response.cookie("foo", "bar", 3600, true);      // secure cookie
response.removeCookie("foo");                   // remove cookie

request.session(true)                            // create and return session
request.session().attribute("user")              // Get session attribute 'user'
request.session().attribute("user", "foo")       // Set session attribute 'user'
request.session().removeAttribute("user", "foo") // Remove session attribute 'user'
request.session().attributes()                   // Get all session attributes
request.session().id()                           // Get session id
request.session().isNew()                        // Check is session is new
request.session().raw()                          // Return servlet object

halt();

halt(401);

halt("This is the body");

halt(401, "Go away!");

before((request, response) -> {
    boolean authenticated;
    // ... check if authenticated
    if (!authenticated) {
        halt(401, "You are not welcome here");
    }
});

after((request, response) -> {
    response.header("foo", "set by after filter");
});

before("/protected/*", (request, response) -> {
    // ... check if authenticated
    halt(401, "Go Away!");
});

response.redirect("/bar");

response.redirect("/bar", 301); // moved permanently

get("/throwexception", (request, response) -> {
    throw new NotFoundException();
});

exception(NotFoundException.class, (e, request, response) -> {
    response.status(404);
    response.body("Resource not found");
});

staticFileLocation("/public"); // Static files

externalStaticFileLocation("/var/www/public"); // Static files

import com.google.gson.Gson;

public class JsonTransformer implements ResponseTransformer {

    private Gson gson = new Gson();

    @Override
    public String render(Object model) {
        return gson.toJson(model);
    }

}

get("/hello", "application/json", (request, response) -> {
    return new MyMessage("Hello World");
}, new JsonTransformer());

<dependency>
    <groupId>com.sparkjava</groupId>
    <artifactId>spark-template-freemarker</artifactId>
    <version>2.0.0</version>
</dependency>

<dependency>
    <groupId>com.sparkjava</groupId>
    <artifactId>spark-template-velocity</artifactId>
    <version>2.0.0</version>
</dependency>

<dependency>
    <groupId>com.sparkjava</groupId>
    <artifactId>spark-template-mustache</artifactId>
    <version>1.0.0</version>
</dependency>

setPort(9090); // Spark will run on port 9090

<filter>
    <filter-name>SparkFilter</filter-name>
    <filter-class>spark.servlet.SparkFilter</filter-class>
    <init-param>
        <param-name>applicationClass</param-name>
        <param-value>com.company.YourApplication</param-value>
    </init-param>
</filter>

<filter-mapping>
    <filter-name>SparkFilter</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

mvn javadoc:javadoc