java 具有弹簧启动和清除缓存方法的番石榴缓存

Posted 2021-05-08

        <dependency>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
            <version>18.0</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context-support</artifactId>
            <version>4.1.7.RELEASE</version>
        </dependency>

@Service
public class CachedService extends WebServiceGatewaySupport implements CachedService {

    @Inject
    private RestTemplate restTemplate;


    @Cacheable(CacheConfig.CACHE_ONE)
    public String getCached() {

        HttpHeaders headers = new HttpHeaders();
        headers.setContentType(MediaType.APPLICATION_JSON);

        HttpEntity<String> reqEntity = new HttpEntity<>("url", headers);

        ResponseEntity<String> response;

        String url = "url";
        response = restTemplate.exchange(
                url,
                HttpMethod.GET, reqEntity, String.class);

        return response.getBody();
    }


}

//Used for manually clearing the cache

@Controller
@RequestMapping("/")
public class CacheController {

    @CacheEvict(value = CacheConfig.CACHE_ONE, allEntries = true)
    @RequestMapping(value = "/clearCache", method = RequestMethod.GET)
    public ResponseEntity<String> clearCache() {
        return new ResponseEntity<String>("Cache Cleared", HttpStatus.OK);
    }
}

import com.google.common.cache.CacheBuilder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.cache.CacheManager;
import org.springframework.cache.annotation.CachingConfigurer;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.cache.guava.GuavaCache;
import org.springframework.cache.interceptor.CacheErrorHandler;
import org.springframework.cache.interceptor.CacheResolver;
import org.springframework.cache.interceptor.KeyGenerator;
import org.springframework.cache.interceptor.SimpleKeyGenerator;
import org.springframework.cache.support.SimpleCacheManager;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import java.util.Arrays;
import java.util.concurrent.TimeUnit;

@Configuration
@EnableCaching
public class CacheConfig implements CachingConfigurer {

    public final static String CACHE_ONE = "cacheOne";
    public final static String CACHE_TWO = "cacheTwo";

    private final Logger log = LoggerFactory
            .getLogger(CacheConfig.class);

    @Bean
    @Override
    public CacheManager cacheManager() {
        log.info("Initializing simple Guava Cache manager.");
        SimpleCacheManager cacheManager = new SimpleCacheManager();

        GuavaCache cache1 = new GuavaCache(CACHE_ONE, CacheBuilder.newBuilder()
                .expireAfterWrite(60, TimeUnit.MINUTES)
                .build());

        GuavaCache cache2 = new GuavaCache(CACHE_TWO, CacheBuilder.newBuilder()
                .expireAfterWrite(60, TimeUnit.SECONDS)
                .build());

        cacheManager.setCaches(Arrays.asList(cache1,cache2));

        return cacheManager;
    }

    @Override
    public CacheResolver cacheResolver() {
        return null;
    }

    @Bean
    @Override
    public KeyGenerator keyGenerator() {
        return new SimpleKeyGenerator();
    }

    @Override
    public CacheErrorHandler errorHandler() {
        return null;
    }
}