他本来是做测试的，啥都不懂  
  
【 在 shaolin (我的大小宝贝儿...) 的大作中提到: 】
:  改改不就行了。
:  类点进去看看数据结构，比着拼个。
:  
:  你这啥都伸手要啊？
--
FROM 223.104.3.*

你的方法返回流陈工，就结束了

只不过网络上传输文件的内容这件事情（真正的把数据流传递给浏览器端）并没有结束，

这种情况下要统计时间可能要用一个异步结束callback才行

【 在 feng321 的大作中提到: 】
: [code=java]
: // 设置响应头
:                         HttpHeaders headers = new HttpHeaders();
: ...................
--
FROM 61.69.255.*

这统计的是把文件写入对象里的时间，return之后才开始传输

【 在 feng321 的大作中提到: 】
: [code=java]
: // 设置响应头
:                         HttpHeaders headers = new HttpHeaders();
: ...................
--
FROM 122.115.35.*

没写过，你试试chatgpt的回答吧

import java.io.IOException;
import java.io.OutputStream;
import java.util.function.Consumer;

public class TimedOutputStream extends OutputStream {
    private final OutputStream delegate;
    private final Consumer<Long> completionCallback;
    private final long startTime;

    public TimedOutputStream(OutputStream delegate, Consumer<Long> completionCallback) {
        this.delegate = delegate;
        this.completionCallback = completionCallback;
        this.startTime = System.currentTimeMillis();
    }

    @Override
    public void write(int b) throws IOException {
        delegate.write(b);
    }

    @Override
    public void close() throws IOException {
        delegate.close();
        long endTime = System.currentTimeMillis();
        long timeConsumed = endTime - startTime;
        completionCallback.accept(timeConsumed);
    }
}


import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.servlet.mvc.method.annotation.ResponseBodyEmitter;

import java.io.OutputStream;
import java.util.concurrent.Executors;

@RestController
@RequestMapping("/download")
public class FileDownloadController {

    @GetMapping("/stream")
    public ResponseBodyEmitter streamData() {
        ResponseBodyEmitter emitter = new ResponseBodyEmitter();

        // Wrap the emitter's OutputStream with the TimedOutputStream
        OutputStream outputStream = new TimedOutputStream(emitter.getOutputStream(),
            timeConsumed -> {
                // Handle completion here, e.g., logging the time consumed
                System.out.println("Time consumed: " + timeConsumed + " ms");
            });

        // Simulate streaming data (replace with your actual data source)
        Executors.newSingleThreadExecutor().submit(() -> {
            try {
                for (int i = 0; i < 10; i++) {
                    outputStream.write(("Data " + i + "\n").getBytes());
                    Thread.sleep(500); // Simulate data processing
                }
            } catch (Exception e) {
                emitter.completeWithError(e);
            } finally {
                try {
                    outputStream.close();
                } catch (IOException e) {
                    emitter.completeWithError(e);
                }
            }
            emitter.complete();
        });

        return emitter;
    }
}



【 在 feng321 的大作中提到: 】
: 能给个可以跑的样例代码吗？真是不太会。。。。
--
FROM 61.69.255.*