API дуудах жишээ client - Java - (2 files : API.java, Main.java)

API.java

package mn.artlab.api.client;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.OutputStream;

import java.net.HttpURLConnection;
import java.net.URL;

import java.util.HashMap;
import java.util.Map;


public class API {
    public static final String BASE_URL = "https://api.artlab.mn/";

    public API() {
        super();
    }

    public static Result get(String path, Map<String, String> headers) {
        return call("GET", path, null, headers);
    }

    public static Result post(String path, String body, Map<String, String> headers) {
        return call("POST", path, body, headers);
    }

    private static Result call(String method, String path, String body, Map<String, String> headers) {
        HttpURLConnection conn = null;
        try {
            URL url = new URL(BASE_URL + path);
            conn = (HttpURLConnection) url.openConnection();

            conn.setDoOutput(true);
            conn.setRequestMethod(method);
            conn.setRequestProperty("Content-Type", "application/json");

            if (headers != null) {
                for (Map.Entry<String, String> entry : headers.entrySet()) {
                    conn.setRequestProperty(entry.getKey(), entry.getValue());
                }
            }

            if (body != null) {
                OutputStream os = conn.getOutputStream();
                os.write( body.getBytes() );
                os.flush();
            }

            if (conn.getResponseCode() != HttpURLConnection.HTTP_OK) {
                return new Result(conn.getResponseCode());
            }

            BufferedReader br = new BufferedReader(
                                    new InputStreamReader((conn.getInputStream())));

            StringBuilder value = new StringBuilder();
            String output = br.readLine();
            while (output != null) {
                value.append(output).append("\n");
                output = br.readLine();
            }

            return new Result(conn.getResponseCode(), value.toString(), conn.getHeaderField("Authorization"));
        } catch (Exception e) {
            throw new RuntimeException(e);
        } finally {
            if (conn != null) {
                conn.disconnect();
            }
        }
    }

    public static Builder builder(String path) {
        return new Builder().path(path);
    }

    public static class Result {
        public final int code;
        public final String result;
        public final String authorization;

        public Result(int code) {
            this(code, null, null);
        }

        public Result(int code, String result, String authorization) {
            this.code = code;
            this.result = result;
            this.authorization = authorization;
        }
    }

    public static class Builder {
        private String path;
        private String method;
        private String inputParam;
        private Map<String, String> headers = new HashMap<>();

        public Builder path(String path) {
            this.path = path;
            return this;
        }

        public Builder authorization(String authorization) {
            headers.put("Authorization", authorization);
            return this;
        }

        public Builder method(String method) {
            this.method = method;
            return this;
        }

        public Builder input(String inputParam) {
            this.inputParam = inputParam;
            return this;
        }

        public Result call() {
            return API.call(method, path, inputParam, headers);
        }

        public Result get() {
            return method("GET").call();
        }

        public Result post() {
            return method("POST").call();
        }
    }
}

Main.java

package mn.artlab.api.client;

public class Main {

    public static void main(String[] args) {
        final String TEMPLATE = ("{" +
                "`username`:`@user`," +
                "`password`:`@pass`," +
                    "`type`:`@type`" +
            "}").replace('`', '"');

        // Хэрэглэгчийн мэдээлэл. ArtLab-с авна.
        final String username = "username-from-artlab";
        final String password = "password-from-artlab";
        final String type     = "type-from-artlab";

        // login хийх
        API.Result r0 = API.builder("auth/login").input(TEMPLATE
            .replace("@user", username)
            .replace("@pass", password)
            .replace("@type", type)).post();

        // login хийж чадсан эсэхээ шалгах
        // бусад resource-ууд руу хандахдаа иймэрхүү байдлаар шалгана
        API.Result r1 = API.builder("auth/check").authorization(r0.authorization).get();
        System.out.println(r1.result);
    }

}