* WeakReference} (by default, strong references are used).
   *
   * <p>Weak values will be garbage collected once they are weakly reachable. This makes them a poor
   * candidate for caching.
   *
   * <p><b>Warning:</b> when this method is used, the resulting map will use identity ({@code ==})
   * comparison to determine equality of values. This technically violates the specifications of the

    builder.build(CacheLoader.from(Suppliers.ofInstance(null)));
  }

  public void testDisableCaching() {
    // Functional test: assert that CacheBuilderSpec.disableCaching()
    // disables caching.  It's irrelevant how it does so.
    CacheBuilder<Object, Object> builder = CacheBuilder.from(CacheBuilderSpec.disableCaching());
    Object key = new Object();
    Object value = new Object();

    response1.close()

    // Force a fresh connection for the next request.
    client.connectionPool.evictAll()

    // Confirm that a second request also succeeds. This should detect caching problems.
    server.enqueue(
      MockResponse
        .Builder()
        .body("def")
        .onResponseEnd(ShutdownConnection)
        .build(),
    )
    val call2 =
      client.newCall(

        }
      }

      static class Gist {
        Map<String, GistFile> files;
      }

      static class GistFile {
        String content;
      }
    ```

### Response Caching ([.kt][CacheResponseKotlin], [.java][CacheResponseJava])

    /** Cache key for cache message */
    protected static final String CACHE_MSG = "cache_msg";

    /** Pattern for matching local file paths */
    protected static final Pattern LOCAL_PATH_PATTERN = Pattern.compile("^file:/+[a-zA-Z]:");

    /** Pattern for matching shared folder paths */
    protected static final Pattern SHARED_FOLDER_PATTERN = Pattern.compile("^file:/+[^/]\\.");

                // Clean release
                releaseHandle(handle);
                break;
        }
    }
}
```

## 10. Performance Considerations

### 10.1 Handle Caching Strategy
```java
public class HandleCache {
    private final int maxHandles = 1000;
    private final LinkedHashMap<String, HandleInfo> lruCache;
    
    public HandleCache() {

import jcifs.CIFSContext;
import jcifs.DfsReferralData;
import jcifs.DfsResolver;
import jcifs.SmbTransport;
import jcifs.internal.dfs.DfsReferralDataImpl;
import jcifs.internal.dfs.DfsReferralDataInternal;

/**
 * Caching DFS resolver implementation
 *
 *
 * <p>This class is intended for internal use.</p>
 */
public class DfsImpl implements DfsResolver {

     */
    public SmbTreeHandle getTreeHandle() throws CIFSException {
        return ensureTreeConnected();
    }

    /**
     * {@inheritDoc}
     * Optimized to provide better resource cleanup with caching benefits.
     *
     * @see java.lang.AutoCloseable#close()
     */
    @Override
    public synchronized void close() {
        final SmbTreeHandleImpl th = this.treeHandle;
        if (th != null) {

been, leading to rare cases of infinite retries. Please upgrade to this release!

 *  Fix: don't return stale DNS entries in `DnsOverHttps`. We were caching DNS results indefinitely
    rather than the duration specified in the response's cache-control header.
 *  Fix: Verify certificate IP addresses in canonical form. When a server presents a TLS certificate

## Provider-specific Notes

* AWS
  * Support for ap-northeast-2 region (Seoul)
  * Allow cross-region image pulling with ECR
  * More reliable kube-up/kube-down
  * Enable ICMP Type 3 Code 4 for ELBs
  * ARP caching fix
  * Use /dev/xvdXX names
  * ELB:
    * ELB proxy protocol support 
	* mixed plaintext/encrypted ports support in ELBs
    * SSL support for ELB listeners
  * Allow VPC CIDR to be specified (experimental)