使用缓存构建更快的 Web 应用程序

jcs.default=jcs.default.cacheattributes=org.apache.jcs.engine.CompositeCacheAttributes
jcs.default.cacheattributes.MaxObjects=1000
jcs.default.cacheattributes.MemoryCacheName=
org.apache.jcs.engine.memory.lru.LRUMemoryCache

jcs.default=DISK_REGION
jcs.default.cacheattributes=org.apache.jcs.engine.CompositeCacheAttributes
jcs.default.cacheattributes.MaxObjects=1000
jcs.default.cacheattributes.MemoryCacheName=
org.apache.jcs.engine.memory.lru.LRUMemoryCache

jcs.region.OUR_REGION=DISK_REGION
jcs.region.OUR_REGION.cacheattributes=org.apache.jcs.engine.CompositeCacheAttributes
jcs.region.OUR_REGION.cacheattributes.MaxObjects=1000
jcs.region.OUR_REGION.cacheattributes.MemoryCacheName=
org.apache.jcs.engine.memory.lru.LRUMemoryCache
jcs.region.OUR_REGION.cacheattributes.UseMemoryShrinker=true
jcs.region.OUR_REGION.cacheattributes.MaxMemoryIdleTimeSeconds=3600
jcs.region.OUR_REGION.cacheattributes.ShrinkerIntervalSeconds=60
jcs.region.OUR_REGION.cacheattributes.MaxSpoolPerRun=500
jcs.region.OUR_REGION.elementattributes=org.apache.jcs.engine.ElementAttributes
jcs.region.OUR_REGION.elementattributes.IsEternal=false

jcs.auxiliary.DISK_REGION=org.apache.jcs.auxiliary.disk.indexed.IndexedDiskCacheFactory
jcs.auxiliary.DISK_REGION.attributes=
org.apache.jcs.auxiliary.disk.indexed.IndexedDiskCacheAttributes
jcs.auxiliary.DISK_REGION.attributes.DiskPath=c:/jcs/disk_region
jcs.auxiliary.DISK_REGION.attributes.maxKeySize=100000

// Initialize the JCS object and get an instance of the default cache region
JCS cache = JCS.getInstance("default");

// Set up
String key = "key0";
String value = "value0";

// Place a new object in the cache
cache.put(key, value);

// Retrieve a cached object
String cachedData = (String)cache.get(key);

// Retrieve a cached object
String cachedData = (String)cache.get(key);
// Check if the retrieval worked
if (cachedData != null) {
// The cachedData is valid and can be used
System.out.println("Valid cached Data: " + cachedData);
}

// Dispose of a specific cached item
cache.remove(key);

// Dispose of all cache data
cache.clear();

// Dispose of the cache region
cache.dispose();

package com.ibm.developerWorks.objects;

import java.io.Serializable;
import java.util.Date;

public class BlogObject implements Serializable {
private static final long serialVersionUID = 6392376146163510046L;
private int blogId;
private String author;
private Date date;
private String title;
private String content;

public BlogObject(int blogId, String author, Date date, String title, String content) {
this.blogId = blogId;
this.author = author;
this.date = date;
this.title = title;
this.content = content;
}

public int getBlogId() {
return this.blogId;
}

public String getAuthor() {
return this.author;
}

public Date getDate() {
return this.date;
}

public String getTitle() {
return this.title;
}

public String getContent() {
return this.content;
}
}

public BlogObject getBlog(int id) {
BlogObject blog = null;

try {
blogCache = JCS.getInstance(blogCacheRegion);
blog = (BlogObject)blogCache.get(id);
} catch (CacheException ce) {
blog = null;
}

if (blog == null) {
blog = DatabaseManager.getBlog(id);
this.setBlog(
blog.getBlogId(),
blog.getAuthor(),
blog.getDate(),
blog.getTitle(),
blog.getContent()
);
}

return blog;
}

public boolean setBlog(int bId, String author, Date date, String title, String content) {
BlogObject blog = new BlogObject(bId, author, date, title, content);

try {
blogCache = JCS.getInstance(blogCacheRegion);
blogCache.put(bId, blog);
return true;
} catch (CacheException ce) {
return false;
}
}

public boolean cleanBlog(int blogId) {
try {
blogCache = JCS.getInstance(blogCacheRegion);
blogCache.remove(blogId);
} catch (CacheException ce) {
return false;
}
return true;
}

public boolean cleanBlog() {
try {
blogCache = JCS.getInstance(blogCacheRegion);
blogCache.clear();
} catch (CacheException ce) {
return false;
}
return true;
}

try {
JCSAdminBean admin = new JCSAdminBean();
LinkedList linkedList = admin.buildElementInfo(regionName);
ListIterator iterator = linkedList.listIterator();

while (iterator.hasNext()) {
CacheElementInfo info = (CacheElementInfo)iterator.next();
System.out.println("Key: " + info.getKey());
System.out.println("Creation Time: " + info.getCreateTime());
System.out.println("Maximum Life (seconds): " + info.getMaxLifeSeconds());
System.out.println("Expires in (seconds): " + info.getExpiresInSeconds());
}
} catch (Exception e) {
}

try {
JCSAdminBean admin = new JCSAdminBean();
LinkedList linkedList = admin.buildCacheInfo();
ListIterator iterator = linkedList.listIterator();

while (iterator.hasNext()) {
CacheRegionInfo info = (CacheRegionInfo)iterator.next();
CompositeCache compCache = info.getCache();
System.out.println("Cache Name: " + compCache.getCacheName());
System.out.println("Cache Type: " + compCache.getCacheType());
System.out.println("Cache Misses (not found): " + compCache.getMissCountNotFound());
System.out.println("Cache Misses (expired): " + compCache.getMissCountExpired());
System.out.println("Cache Hits (memory): " + compCache.getHitCountRam());
System.out.println("Cache Updates: " + compCache.getUpdateCount());
}
} catch (Exception e) {
}