一、出现问题的原因

根据访问的网站的管理员的提示，对访问的参数进行调整，模拟浏览器访问。
在这里插入图片描述

二、模拟浏览器访问

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
public class holidayTest {
	public static void main(String[] args) {
		String methodUrl = "http://timor.tech/api/holiday/year/2021/";
		HttpURLConnection connection = null;
		BufferedReader reader = null;
		String line = null;
		try {
			URL url = new URL(methodUrl);
			// 根据URL生成HttpURLConnection
			connection = (HttpURLConnection) url.openConnection();
			connection.setRequestMethod("GET");// 默认GET请求
			connection.setDoInput(true);
			connection.setDoOutput(true);
			connection.setRequestProperty("Content-Type", "application/json;charset=UTF-8");
			connection.setRequestProperty("accept", "*/*");
            connection.setRequestProperty("connection", "Keep-Alive");
            //模拟postman
			connection.setRequestProperty("User-Agent", "PostmanRuntime/7.26.8");
			
			connection.connect();// 建立TCP连接
			int type = connection.getResponseCode();
			if (type == HttpURLConnection.HTTP_OK) {
				// 发送http请求
				reader = new BufferedReader(new InputStreamReader(connection.getInputStream(), "UTF-8"));
				StringBuilder result = new StringBuilder();
				// 循环读取流
				while ((line = reader.readLine()) != null) {
					result.append(line).append(System.getProperty("line.separator"));// "\n"
				}
				System.out.println(result.toString());
			}
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			try {
				reader.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
			connection.disconnect();
		}
	
	}
}

三、以下代码出现：403

以下代码需要模拟浏览器的访问才能解决问题。

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
/**
 * @author ldg
 * 访问节假日接口
 */
public class holidayTest {
	public static void main(String[] args) {
		String methodUrl = "http://timor.tech/api/holiday/year/2021/";
		HttpURLConnection connection = null;
		BufferedReader reader = null;
		String line = null;
		try {
			URL url = new URL(methodUrl);
			// 根据URL生成HttpURLConnection
			connection = (HttpURLConnection) url.openConnection();
			connection.setRequestMethod("GET");// 默认GET请求
			connection.connect();// 建立TCP连接
			
			int type = connection.getResponseCode();
			if (type == HttpURLConnection.HTTP_OK) {
				// 发送http请求
				reader = new BufferedReader(new InputStreamReader(connection.getInputStream(), "UTF-8"));
				StringBuilder result = new StringBuilder();
				// 循环读取流
				while ((line = reader.readLine()) != null) {
					result.append(line).append(System.getProperty("line.separator"));// "\n"
				}
				System.out.println(result.toString());
			}
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			try {
				reader.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
			connection.disconnect();
		}
	}
}