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# Caching
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HTTP response caching with filesystem storage, cache control directives, and LRU eviction.
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## Capabilities
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### Cache
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HTTP response cache using filesystem storage with LRU eviction.
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```java { .api }
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public final class Cache {
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    public Cache(File directory, long maxSize);
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    public void initialize() throws IOException;
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    public void delete() throws IOException;
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    public void evictAll() throws IOException;
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    public Iterator<String> urls() throws IOException;
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    public long getSize() throws IOException;
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    public long getMaxSize();
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    public void flush() throws IOException;
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    public void close() throws IOException;
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    public File getDirectory();
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    public boolean isClosed();
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    public int getNetworkCount();
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    public int getHitCount();
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    public int getRequestCount();
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}
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```
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### CacheControl
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Cache-Control header directives for request and response caching policies.
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```java { .api }
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public final class CacheControl {
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    public static final CacheControl FORCE_NETWORK;
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    public static final CacheControl FORCE_CACHE;
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    public static CacheControl parse(Headers headers);
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    public boolean noCache();
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    public boolean noStore();
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    public int maxAgeSeconds();
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    public int sMaxAgeSeconds();
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    public boolean isPrivate();
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    public boolean isPublic();
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    public boolean mustRevalidate();
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    public int maxStaleSeconds();
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    public int minFreshSeconds();
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    public boolean onlyIfCached();
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    public boolean noTransform();
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    public static final class Builder {
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        public Builder();
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        public Builder noCache();
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        public Builder noStore();
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        public Builder maxAge(int maxAge, TimeUnit timeUnit);
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        public Builder maxStale(int maxStale, TimeUnit timeUnit);
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        public Builder minFresh(int minFresh, TimeUnit timeUnit);
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        public Builder onlyIfCached();
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        public Builder noTransform();
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        public CacheControl build();
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    }
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}
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```
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**Usage Examples:**
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```java
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// Set up cache
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File cacheDir = new File(context.getCacheDir(), "http-cache");
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Cache cache = new Cache(cacheDir, 10 * 1024 * 1024); // 10 MB
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client.setCache(cache);
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// Force network request
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Request request = new Request.Builder()
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    .url("https://api.example.com/data")
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    .cacheControl(CacheControl.FORCE_NETWORK)
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    .build();
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// Use cache only
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Request cacheOnlyRequest = new Request.Builder()
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    .url("https://api.example.com/data")
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    .cacheControl(CacheControl.FORCE_CACHE)
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    .build();
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// Custom cache control with builder
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CacheControl customCacheControl = new CacheControl.Builder()
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    .maxAge(60, TimeUnit.SECONDS)       // Cache for 60 seconds
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    .maxStale(300, TimeUnit.SECONDS)    // Accept stale cache up to 5 minutes
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    .minFresh(30, TimeUnit.SECONDS)     // Require fresh data for 30 seconds
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    .build();
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Request customRequest = new Request.Builder()
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    .url("https://api.example.com/data")
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    .cacheControl(customCacheControl)
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    .build();
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// No cache request
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CacheControl noCache = new CacheControl.Builder()
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    .noCache()
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    .noStore()
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    .build();
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// Cache monitoring
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System.out.println("Cache hits: " + cache.getHitCount());
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System.out.println("Network requests: " + cache.getNetworkCount());
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System.out.println("Total requests: " + cache.getRequestCount());
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System.out.println("Cache size: " + cache.getSize() + " bytes");
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```