Details the technical principles and usage of the "Disk Lru Cache" framework in the Java class library

The "DISK LRU CACHE" framework in the Java class library is a tool for caching data to the disk. It uses the LRU (recently used) algorithm to manage the data in the cache, and the data is persisted to the disk for the disk so that so that soQuick access when needed. Technical principle: 1. LRU cache algorithm: The LRU algorithm is based on the principle of "minimum use recently." The most recent data used out of the cache can always keep the most commonly accessible data in the cache.This algorithm is suitable for a large number of cache data and limited memory. 2. Disk persistence: DISK LRU CACHE continues the cache data to the disk, so that the data can be restored from the disk in the application restart, insufficient memory, or other cases.It uses a file system to store data, and each cache item is stored in a separate file. Instructions: The following is a simple step to use the Disk Lru Cache framework: 1. Introduction dependencies: First of all, you need to add Disk Lru Cache to the project's Maven or Gradle configuration file. 2. Create Disk Lru Cache instance: Create a DISK LRU CACHE instance using the Builder mode. DiskLruCache cache = DiskLruCache.create(cacheDir, appVersion, valueCount, maxSize); Among them, CacheDir is a directory for storing caching files; AppVersion is an application version number that is used to distinguish when the cache file format changes; ValueCount is the number of files corresponding to each cache item; MaxSize is the maximum limit size of the cache cache.Essence 3. Write data to the cache: Start a cache editing operation by calling the Edit () method of Disk Lru Cache instance. DiskLruCache.Editor editor = cache.edit(key); OutputStream outputStream = editor.newOutputStream(0); outputStream.write(data); outputStream.close(); editor.commit(); In this example, we started a cache editing operation through the Edit () method and specified a unique key.Then obtain an output stream through the newoutPutstream () method and write the data into the output stream.Finally, call the Commit () method to submit the cache operation. 4. Read data from the cache: Get a cache bar by calling the GET () method of Disk Lru Cache instance. DiskLruCache.Snapshot snapshot = cache.get(key); if (snapshot != null) { InputStream inputStream = snapshot.getInputStream(0); byte[] data = readDataFromInputStream(inputStream); inputStream.close(); } In this example, we obtained a cache bar through the get () method and check whether it is NULL.If you are not NULL, we can get an input stream through the getInputStream () method and read data from the input stream. Summarize: The DISK LRU Cache framework provides a simple and efficient way to cache data on the disk and quickly access when needed.By following the above steps, you can easily integrate and use the framework to improve the performance and response speed of the application.