怎么使用java发送httpget请求

使用Java发送HttpGet请求的步骤如下：

1. 导入所需的类：

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

2. 创建URL对象，指定要发送请求的URL：

URL url = new URL("http://example.com");

3. 打开连接并创建HttpURLConnection对象：

HttpURLConnection connection = (HttpURLConnection) url.openConnection();

4. 设置请求方法为GET：

connection.setRequestMethod("GET");

5. 获取响应码：

int responseCode = connection.getResponseCode();

6. 根据响应码判断请求是否成功：

if (responseCode == HttpURLConnection.HTTP_OK) {
BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String inputLine;
StringBuilder response = new StringBuilder();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
// 处理响应数据
System.out.println(response.toString());
} else {
System.out.println("请求失败");
}

7. 关闭连接：

connection.disconnect();

完整的示例代码如下：

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
public class HttpGetExample {
public static void main(String[] args) {
try {
URL url = new URL("http://example.com");
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
int responseCode = connection.getResponseCode();
if (responseCode == HttpURLConnection.HTTP_OK) {
BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String inputLine;
StringBuilder response = new StringBuilder();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
System.out.println(response.toString());
} else {
System.out.println("请求失败");
}
connection.disconnect();
} catch (Exception e) {
e.printStackTrace();
}
}
}

注意：上述示例代码中的URL为示例URL，实际使用时需要替换为你要发送请求的URL。