Guava Cache LoadingCache 之 refreshAfterWrites和expireAfterWrite区别_loadingcache refreshafterwrite(1)

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* 加入cache的数据
*/
private Map<String, String> setData() {
Map<String, String> result = new HashMap<>();

	result.put("result1", "小明");
	result.put("result2", "小黑");
	result.put("result3", "小白");
	result.put("result4", "小黄");

	return result;
}

/\*\*

* 构建缓存对象
*/
private void buildCache() {

	cache = CacheBuilder.newBuilder().refreshAfterWrite(8, TimeUnit.SECONDS)
			.build(new CacheLoader<String, Map<String, String>>() {
				@Override
				public Map<String, String> load(String s) throws Exception {
					System.out.println("load ...");
					return setData();
				}

				@Override
				public ListenableFuture<Map<String, String>> reload(String key, Map<String, String> oldValue)
						throws Exception {
					System.out.println("reload ...");
					ListenableFutureTask<Map<String, String>> task = ListenableFutureTask
							.create(new Callable<Map<String, String>>() {
								@Override
								public Map<String, String> call() throws Exception {
									return setData();
								}
							});
					executorService.execute(task);
					return task;
				}
			});

}

/\*\*

* 测试
*/
public static void main(String[] args) {

	LoadingCacheDemo demo = new LoadingCacheDemo();
	demo.buildCache();

	Runnable runnable1 = () -> {
		for (int i = 0; i < 100; i++) {
			try {
				System.out.println("Runnable1 Before Get Cache");
				System.out.println("Runnable1 " + demo.cache.get("test"));
				System.out.println("Runnable1 After Get Cache");
				Thread.currentThread().sleep(1000);
			} catch (ExecutionException e) {
				e.printStackTrace();
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
		}
	};
	Runnable runnable2 = () -> {
		for (int i = 0; i < 100; i++) {
			try {
				System.out.println("Runnable2 Before Get Cache");
				System.out.println("Runnable2 " + demo.cache.get("test"));
				System.out.println("Runnable2 After Get Cache");
				Thread.currentThread().sleep(1000);
			} catch (ExecutionException e) {
				e.printStackTrace();
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
		}
	};
	Thread thread1 = new Thread(runnable1);
	Thread thread2 = new Thread(runnable2);
	thread1.start();
	thread2.start();

}

}

## expireAfterWrite 例子

package com.cjt.demo;

import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;

import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;

public class CacheDemo2 {

private static Cache<String, String> cache = CacheBuilder.newBuilder().maximumSize(1).
        expireAfterWrite(10, TimeUnit.SECONDS).build();

public static void main(String[] args) {

    try {

        Runnable runnable1 = () -> {
            for (int i = 0; i < 10; i++) {
                try {
                    String str = cache.get("123", new Callable<String>() {
                        public String call() throws Exception {
                            cache.put("123","123");
                            return "111111111111111";
                        }
                    });
                    System.out.println(str);

                    Thread.currentThread().sleep(1000);
                } catch (ExecutionException e) {
                    e.printStackTrace();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        };
        Runnable runnable2 = () -> {
            for (int i = 0; i < 10; i++) {
                try {
                    System.out.println(cache.get("456", new Callable<String>() {
                        public String call() throws Exception {
                            cache.put("456","456");
                            return "222222222222222";
                        }
                    }));
                    Thread.currentThread().sleep(1000);
                } catch (ExecutionException e) {
                    e.printStackTrace();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        };
        Thread thread1 = new Thread(runnable1);
        Thread thread2 = new Thread(runnable2);
        thread1.start();
        thread2.start();

    } catch (Exception e) {
        e.printStackTrace();
    }
}

}

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**由于文件比较多，这里只是将部分目录截图出来，全套包含大厂面经、学习笔记、源码讲义、实战项目、大纲路线、讲解视频，并且后续会持续更新**

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