java -- 入门

package com.zte.ws.dev;

import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;

import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

@Slf4j
@Component
public class Practise {
    private final Map<String,String> dataMap = new ConcurrentHashMap<>();;

    public Practise() {
        log.info("Practise initialized with ConcurrentHashMap");
    }

    public void Func(){
        this.dataMap.put("key1","value1");
    }

    public void PrintDataMap() {
        System.out.println("=== DataMap Content ===");
        this.dataMap.forEach((k, v) ->
                System.out.println("Key: " + k + ", Value: " + v)
        );
        System.out.println("Size: " + this.dataMap.size());
    }
}

package com.zte.ws.dev;

public class PractiseTest {

    public static void main(String[] args) {
        // ✅ 直接 new 实例（绕过 Spring）
        Practise practise = new Practise();

        // ✅ 调用方法
        practise.Func();

        // ✅ 输出结果
        practise.PrintDataMap();
    }
}