ca.nrc.cadc.reg.client

Class CachingFile

java.lang.Object

ca.nrc.cadc.reg.client.CachingFile

public class CachingFile
extends java.lang.Object

This class will handle the caching of a file based on a remote source. Strategy for caching:

• 1. Open existing file and check timestamp.
• 2. If not expired, open file and return to user
• 3. Otherwise: read capabilities from web service
• 4. Write new capabilities to temp file
• 5. Atomically move temp file to real file
• 6. Return these refreshed capabilities

Constructor Summary

Constructors

Constructor and Description
CachingFile(java.io.File localCache, java.net.URL remoteSource) Construct a caching file with the local file and the remote source.
CachingFile(java.io.File localCache, java.net.URL remoteSource, long expirySeconds) Construct a caching file with the local file and the remote source.

Method Summary

Modifier and Type	Method and Description
java.lang.String	getContent()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CachingFile

public CachingFile(java.io.File localCache,
                   java.net.URL remoteSource)

Construct a caching file with the local file and the remote source. Cache is checked for updates every 10 minutes by default.

Parameters:

localCache - Where to keep the cache

remoteSource - Where to get the content

CachingFile

public CachingFile(java.io.File localCache,
                   java.net.URL remoteSource,
                   long expirySeconds)

Construct a caching file with the local file and the remote source.

Parameters:

localCache - Where to keep the cache

remoteSource - Where to get the content

expirySeconds - The number of seconds between cache update checks.

Method Detail

getContent

public java.lang.String getContent()
                            throws java.io.IOException

Throws:

java.io.IOException