[Java]无依赖实现简单HttpServer，并实现基本功能

前言

有时候，我们需要用Java开发一个小的程序，或者只需要实现简单的http监听的server，此时并不想引入太多依赖（比如Spring或者要使用Tomcat等），此时可以使用Java自带的HttpServer来实现简单的web服务器，实现一些基本功能还是没有问题的。

实现

下面分享下代码片段实现HttpServer，代码实现了以下几个功能和要点（详见代码注释）：

实现web server（GET方法）: http://127.0.0.1:8182/hello
如果GET携带参数 http://127.0.0.1:8182/hello?msg=hello&type=1 可以解析参数(queryToMap)
返回中带中文问题
实现简单的Basic Auth认证
实现web server（POST方法）: http://127.0.0.1:8182/post，并解析出参数
返回简单的HTML代码

import com.sun.net.httpserver.BasicAuthenticator;

import com.sun.net.httpserver.HttpContext;

import com.sun.net.httpserver.HttpExchange;

import com.sun.net.httpserver.HttpHandler;

import com.sun.net.httpserver.HttpServer;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.net.InetSocketAddress;

import java.nio.charset.StandardCharsets;

import java.util.HashMap;

import java.util.Map;

import java.util.concurrent.Executors;

public class SimpleHttpServer {

public static void main(String[] args) throws Exception {

// 监听8182端口

HttpServer httpServer = HttpServer.create(new InetSocketAddress(8182), 0);

// http://127.0.0.1:8182/hello

HttpContext cc = httpServer.createContext("/hello", new HelloHandler());

// basic auth 简单验证

cc.setAuthenticator(new AuthVerify("Restricted Area"));

//用lambda方式演示，post方法，并返回简单的HTML(处理中文问题)

httpServer.createContext("/post", httpExchange -> {

InputStream input = httpExchange.getRequestBody();

StringBuilder stringBuilder = new StringBuilder();

new BufferedReader(new InputStreamReader(input))

.lines()

.forEach((String s) -> stringBuilder.append(s).append("\n"));

String response = "<html>\n"

+ "<body>\n"

+ "\n"

+ "<h4>"

+ "收到的参数是："+stringBuilder

+ "</h4>"

+ "</body>\n"

+ "</html> ";

// 如果有中文，response.getBytes 需要加上UTF-8

httpExchange.sendResponseHeaders(200, response.getBytes(StandardCharsets.UTF_8).length);

OutputStream output = httpExchange.getResponseBody();

output.write(response.getBytes(StandardCharsets.UTF_8));

output.flush();

output.close();

httpExchange.close();

});

httpServer.setExecutor(Executors.newCachedThreadPool());

httpServer.start();

}

static class HelloHandler implements HttpHandler {

@Override

public void handle(HttpExchange httpExchange) throws IOException {

String query = httpExchange.getRequestURI().getQuery();

String response = "HelloWorld, 收到的参数是: " + query;

// 可以使用queryToMap(query) 工具方法，把query转成map

httpExchange.sendResponseHeaders(200, response.getBytes(StandardCharsets.UTF_8).length);

OutputStream os = httpExchange.getResponseBody();

// 如果有中文，response.getBytes 需要加上UTF-8

os.write(response.getBytes(StandardCharsets.UTF_8));

os.flush();

os.close();

}

static class AuthVerify extends BasicAuthenticator {

public AuthVerify(String s) {

super(s);

}

@Override

public boolean checkCredentials(String username, String password) {

return "admin".equals(username) && "password".equals(password);

}

public static Map<String, String> queryToMap(String query) {

Map<String, String> result = new HashMap<>();

for (String param : query.split("&")) {

String[] entry = param.split("=");

if (entry.length > 1) {

result.put(entry[0], entry[1]);

} else {

result.put(entry[0], "");

}

return result;

}

import com.sun.net.httpserver.BasicAuthenticator; import com.sun.net.httpserver.HttpContext; import com.sun.net.httpserver.HttpExchange; import com.sun.net.httpserver.HttpHandler; import com.sun.net.httpserver.HttpServer; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.OutputStream; import java.net.InetSocketAddress; import java.nio.charset.StandardCharsets; import java.util.HashMap; import java.util.Map; import java.util.concurrent.Executors; public class SimpleHttpServer { public static void main(String[] args) throws Exception { // 监听8182端口 HttpServer httpServer = HttpServer.create(new InetSocketAddress(8182), 0); // http://127.0.0.1:8182/hello HttpContext cc = httpServer.createContext("/hello", new HelloHandler()); // basic auth 简单验证 cc.setAuthenticator(new AuthVerify("Restricted Area")); //用lambda方式演示，post方法，并返回简单的HTML(处理中文问题) httpServer.createContext("/post", httpExchange -> { InputStream input = httpExchange.getRequestBody(); StringBuilder stringBuilder = new StringBuilder(); new BufferedReader(new InputStreamReader(input)) .lines() .forEach((String s) -> stringBuilder.append(s).append("\n")); String response = "<html>\n" + "<body>\n" + "\n" + "<h4>" + "收到的参数是："+stringBuilder + "</h4>" + "</body>\n" + "</html> "; // 如果有中文，response.getBytes 需要加上UTF-8 httpExchange.sendResponseHeaders(200, response.getBytes(StandardCharsets.UTF_8).length); OutputStream output = httpExchange.getResponseBody(); output.write(response.getBytes(StandardCharsets.UTF_8)); output.flush(); output.close(); httpExchange.close(); }); httpServer.setExecutor(Executors.newCachedThreadPool()); httpServer.start(); } static class HelloHandler implements HttpHandler { @Override public void handle(HttpExchange httpExchange) throws IOException { String query = httpExchange.getRequestURI().getQuery(); String response = "HelloWorld, 收到的参数是: " + query; // 可以使用queryToMap(query) 工具方法，把query转成map httpExchange.sendResponseHeaders(200, response.getBytes(StandardCharsets.UTF_8).length); OutputStream os = httpExchange.getResponseBody(); // 如果有中文，response.getBytes 需要加上UTF-8 os.write(response.getBytes(StandardCharsets.UTF_8)); os.flush(); os.close(); } } static class AuthVerify extends BasicAuthenticator { public AuthVerify(String s) { super(s); } @Override public boolean checkCredentials(String username, String password) { return "admin".equals(username) && "password".equals(password); } } public static Map<String, String> queryToMap(String query) { Map<String, String> result = new HashMap<>(); for (String param : query.split("&")) { String[] entry = param.split("="); if (entry.length > 1) { result.put(entry[0], entry[1]); } else { result.put(entry[0], ""); } } return result; } }

import com.sun.net.httpserver.BasicAuthenticator;
import com.sun.net.httpserver.HttpContext;
import com.sun.net.httpserver.HttpExchange;
import com.sun.net.httpserver.HttpHandler;
import com.sun.net.httpserver.HttpServer;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.InetSocketAddress;
import java.nio.charset.StandardCharsets;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.Executors;

public class SimpleHttpServer {

    public static void main(String[] args) throws Exception {
        // 监听8182端口
        HttpServer httpServer = HttpServer.create(new InetSocketAddress(8182), 0);
        // http://127.0.0.1:8182/hello
        HttpContext cc = httpServer.createContext("/hello", new HelloHandler());
        // basic auth 简单验证
        cc.setAuthenticator(new AuthVerify("Restricted Area"));

        //用lambda方式演示，post方法，并返回简单的HTML(处理中文问题)
        httpServer.createContext("/post", httpExchange -> {
            InputStream input = httpExchange.getRequestBody();
            StringBuilder stringBuilder = new StringBuilder();

            new BufferedReader(new InputStreamReader(input))
                    .lines()
                    .forEach((String s) -> stringBuilder.append(s).append("\n"));

            String response = "<html>\n"
                    + "<body>\n"
                    + "\n"
                    + "<h4>"
                    + "收到的参数是："+stringBuilder
                    + "</h4>"
                    + "</body>\n"
                    + "</html> ";

            // 如果有中文，response.getBytes 需要加上UTF-8
            httpExchange.sendResponseHeaders(200, response.getBytes(StandardCharsets.UTF_8).length);
            OutputStream output = httpExchange.getResponseBody();
            output.write(response.getBytes(StandardCharsets.UTF_8));
            output.flush();
            output.close();

            httpExchange.close();
        });

        httpServer.setExecutor(Executors.newCachedThreadPool());
        httpServer.start();

    }

    static class HelloHandler implements HttpHandler {

        @Override
        public void handle(HttpExchange httpExchange) throws IOException {
            String query = httpExchange.getRequestURI().getQuery();
            String response = "HelloWorld, 收到的参数是: " + query;
            // 可以使用queryToMap(query) 工具方法，把query转成map
            httpExchange.sendResponseHeaders(200, response.getBytes(StandardCharsets.UTF_8).length);
            OutputStream os = httpExchange.getResponseBody();
            // 如果有中文，response.getBytes 需要加上UTF-8
            os.write(response.getBytes(StandardCharsets.UTF_8));
            os.flush();
            os.close();
        }
    }

    static class AuthVerify extends BasicAuthenticator {

        public AuthVerify(String s) {
            super(s);
        }

        @Override
        public boolean checkCredentials(String username, String password) {
            return "admin".equals(username) && "password".equals(password);
        }
    }

    public static Map<String, String> queryToMap(String query) {
        Map<String, String> result = new HashMap<>();
        for (String param : query.split("&")) {
            String[] entry = param.split("=");
            if (entry.length > 1) {
                result.put(entry[0], entry[1]);
            } else {
                result.put(entry[0], "");
            }
        }
        return result;
    }

}

[Java]无依赖实现简单HttpServer，并实现基本功能

前言

实现

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