新闻：Spark 2.7.0 已发布。请试用它并报告任何 bug。
<dependency>
<groupId>com.sparkjava</groupId>
<artifactId>spark-core</artifactId>
<version>2.7.0</version>
</dependency>
重要提示 - 较旧版本的 Spark（低于 2.5.2 的版本）存在一个漏洞。请升级到最新版本。
文档请访问：http://sparkjava.com/documentation
使用问题请使用 带有 “spark-java” 标签的 Stack Overflow
Javadoc：http://javadoc.io/doc/com.sparkjava/spark-core
<dependency>
<groupId>com.sparkjava</groupId>
<artifactId>spark-core</artifactId>
<version>2.7.0</version>
</dependency>
import static spark.Spark.*;
public class HelloWorld {
public static void main(String[] args) {
get("/hello", (request, response) -> "Hello World!");
}
}
查看：http://localhost:4567/hello
请查看并尝试源代码中的示例。 你也可以查看 javadoc。从 github 获取源代码后运行：
mvn javadoc:javadoc
结果将放在 /target/site/apidocs
展示一些基本功能的简单示例
import static spark.Spark.*;
/**
* A simple example just showing some basic functionality
*/
public class SimpleExample {
public static void main(String[] args) {
// port(5678); <- Uncomment this if you want spark to listen to port 5678 instead of the default 4567
get("/hello", (request, response) -> "Hello World!");
post("/hello", (request, response) ->
"Hello World: " + request.body()
);
get("/private", (request, response) -> {
response.status(401);
return "Go Away!!!";
});
get("/users/:name", (request, response) -> "Selected user: " + request.params(":name"));
get("/news/:section", (request, response) -> {
response.type("text/xml");
return "<?xml version=\"1.0\" encoding=\"UTF-8\"?><news>" + request.params("section") + "</news>";
});
get("/protected", (request, response) -> {
halt(403, "I don't think so!!!");
return null;
});
get("/redirect", (request, response) -> {
response.redirect("/news/world");
return null;
});
get("/", (request, response) -> "root");
}
}
一个简单的 CRUD 示例，展示如何创建、获取、更新和删除图书资源
import static spark.Spark.*;
import java.util.HashMap;
import java.util.Map;
import java.util.Random;
/**
* A simple CRUD example showing how to create, get, update and delete book resources.
*/
public class Books {
/**
* Map holding the books
*/
private static Map<String, Book> books = new HashMap<String, Book>();
public static void main(String[] args) {
final Random random = new Random();
// Creates a new book resource, will return the ID to the created resource
// author and title are sent in the post body as x-www-urlencoded values e.g. author=Foo&title=Bar
// you get them by using request.queryParams("valuename")
post("/books", (request, response) -> {
String author = request.queryParams("author");
String title = request.queryParams("title");
Book book = new Book(author, title);
int id = random.nextInt(Integer.MAX_VALUE);
books.put(String.valueOf(id), book);
response.status(201); // 201 Created
return id;
});
// Gets the book resource for the provided id
get("/books/:id", (request, response) -> {
Book book = books.get(request.params(":id"));
if (book != null) {
return "Title: " + book.getTitle() + ", Author: " + book.getAuthor();
} else {
response.status(404); // 404 Not found
return "Book not found";
}
});
// Updates the book resource for the provided id with new information
// author and title are sent in the request body as x-www-urlencoded values e.g. author=Foo&title=Bar
// you get them by using request.queryParams("valuename")
put("/books/:id", (request, response) -> {
String id = request.params(":id");
Book book = books.get(id);
if (book != null) {
String newAuthor = request.queryParams("author");
String newTitle = request.queryParams("title");
if (newAuthor != null) {
book.setAuthor(newAuthor);
}
if (newTitle != null) {
book.setTitle(newTitle);
}
return "Book with id '" + id + "' updated";
} else {
response.status(404); // 404 Not found
return "Book not found";
}
});
// Deletes the book resource for the provided id
delete("/books/:id", (request, response) -> {
String id = request.params(":id");
Book book = books.remove(id);
if (book != null) {
return "Book with id '" + id + "' deleted";
} else {
response.status(404); // 404 Not found
return "Book not found";
}
});
// Gets all available book resources (ids)
get("/books", (request, response) -> {
String ids = "";
for (String id : books.keySet()) {
ids += id + " ";
}
return ids;
});
}
public static class Book {
public String author, title;
public Book(String author, String title) {
this.author = author;
this.title = title;
}
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
}
}
示例展示一个非常简单的（而且有点笨的）身份验证过滤器，它在所有其他资源之前执行
import static spark.Spark.*;
import java.util.HashMap;
import java.util.Map;
/**
* Example showing a very simple (and stupid) authentication filter that is
* executed before all other resources.
*
* When requesting the resource with e.g.
* http://localhost:4567/hello?user=some&password=guy
* the filter will stop the execution and the client will get a 401 UNAUTHORIZED with the content 'You are not welcome here'
*
* When requesting the resource with e.g.
* http://localhost:4567/hello?user=foo&password=bar
* the filter will accept the request and the request will continue to the /hello route.
*
* Note: There is a second "before filter" that adds a header to the response
* Note: There is also an "after filter" that adds a header to the response
*/
public class FilterExample {
private static Map<String, String> usernamePasswords = new HashMap<String, String>();
public static void main(String[] args) {
usernamePasswords.put("foo", "bar");
usernamePasswords.put("admin", "admin");
before((request, response) -> {
String user = request.queryParams("user");
String password = request.queryParams("password");
String dbPassword = usernamePasswords.get(user);
if (!(password != null && password.equals(dbPassword))) {
halt(401, "You are not welcome here!!!");
}
});