Java 将方法作为参数传递
1、前言
在通过WebSocket向浏览器发送数据时,需要发送3种数据到页面上,写3个方法感觉太冗余,故想到了JDK1.8的lambda表达式和Function<T, R>
实现Java把方法作为参数传递
2、上代码
package com.ruoyi.project.front.comService;
import com.ruoyi.project.manage.param_set.mapper.ParamSetMapper;
import com.ruoyi.project.socket.webSocket.BeamWebSocket;
import com.ruoyi.project.socket.webSocket.LighterWebSocket;
import com.ruoyi.project.socket.webSocket.RollerWebSocket;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
import java.util.Timer;
import java.util.TimerTask;
import java.util.function.Function;
@Component
public class SendToWebHelper {
@Autowired
private ParamSetMapper paramSetMapper;
private static int index = 0;
private static Integer hz = 5;
public void sendToWeb() {
sendToWeb("lighter", (s) -> LighterWebSocket.sendMessageToAllClient(s));
sendToWeb("roller", (s) -> RollerWebSocket.sendMessageToAllClient(s));
sendToWeb("beam", (s) -> BeamWebSocket.sendMessageToAllClient(s));
}
private void sendToWeb(String dir, Function<String, String> function) {
String imgFileDir = paramSetMapper.getParamByCode("imgFileDir").getParamValue();
String nginxServer = paramSetMapper.getParamByCode("nginxServer").getParamValue();
File file = new File(imgFileDir + "/" + dir);
if (!file.exists() || file.listFiles() == null || file.listFiles().length <= 0) {
System.out.println(dir + " dir empty");
return;
}
List<String> list = new ArrayList<>();
for (File f1 : file.listFiles()) {
list.add(f1.getName());
}
Timer timer = new Timer();
timer.scheduleAtFixedRate(new TimerTask() {
@Override
public void run() {
try {
String webPath = nginxServer + "/" + dir + "/" + list.get(index) + "";
if (index++ >= list.size() - 1) {
index = 0;
}
function.apply(webPath);
} catch (Exception e) {
e.printStackTrace();
}
}
}, 0, 1000 / hz);
}
}