问题描述：在使用Http Client发送API Get请求时，需要设置Content-Type为application/json;charset=UTF-8，但是在发送请求时出现了问题。

解决方法：可以通过以下几步来解决该问题。

1. 设置请求头的Content-Type为application/json;charset=UTF-8：

HttpClient client = HttpClientBuilder.create().build();
HttpGet request = new HttpGet(url);
request.setHeader("Content-Type", "application/json;charset=UTF-8");

2. 执行请求并获取响应：

HttpResponse response = client.execute(request);

3. 检查响应的状态码，并处理响应结果：

int statusCode = response.getStatusLine().getStatusCode();
if (statusCode == HttpStatus.SC_OK) {
    // 请求成功
    String responseBody = EntityUtils.toString(response.getEntity());
    // 处理响应结果
} else {
    // 请求失败
    // 处理错误情况
}

完整示例代码如下所示：

import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.util.EntityUtils;

public class HttpClientExample {
    public static void main(String[] args) {
        String url = "https://api.example.com/get-data";
        
        try {
            HttpClient client = HttpClientBuilder.create().build();
            HttpGet request = new HttpGet(url);
            request.setHeader("Content-Type", "application/json;charset=UTF-8");
            
            HttpResponse response = client.execute(request);
            
            int statusCode = response.getStatusLine().getStatusCode();
            if (statusCode == HttpStatus.SC_OK) {
                String responseBody = EntityUtils.toString(response.getEntity());
                // 处理响应结果
                System.out.println(responseBody);
            } else {
                // 处理错误情况
                System.out.println("请求失败，状态码：" + statusCode);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

以上代码示例中使用了Apache HttpClient库来发送HTTP请求，并处理响应结果。请根据实际情况进行相应的修改和调整。