CachedFile (JOSM)

java.lang.Object
- org.openstreetmap.josm.io.CachedFile

```
public class CachedFile
extends Object
```
Downloads a file and caches it on disk in order to reduce network load. Supports URLs, local files, and a custom scheme (resource:) to get resources from the current *.jar file. (Local caching is only done for URLs.)
The mirrored file is only downloaded if it has been more than 7 days since last download. (Time can be configured.)
The file content is normally accessed with getInputStream(), but you can also get the mirrored copy with getFile().

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class CachedFile.CachingStrategy
Caching strategy.

Nested Classes
Modifier and Type	Class and Description
`static class`	`CachedFile.CachingStrategy` Caching strategy.

Field Summary

Fields
Modifier and Type	Field and Description
`protected File`	`cacheFile`
`protected CachedFile.CachingStrategy`	`cachingStrategy`
`static long`	`DAYS`
`static long`	`DEFAULT_MAXTIME`
`protected String`	`destDir`
`protected String`	`httpAccept`
`private Map<String,String>`	`httpHeaders`
`protected boolean`	`initialized`
`protected long`	`maxAge`
`protected String`	`name`

Constructor Summary

Constructors
Constructor and Description

CachedFile(String name)
Constructs a CachedFile object from a given filename, URL or internal resource.

Constructors
Constructor and Description
`CachedFile(String name)` Constructs a CachedFile object from a given filename, URL or internal resource.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`private File`	`checkLocal(URL url)`
`private static void`	`checkOfflineAccess(String urlString)`
`static void`	`cleanup(String name)` Clear the cache for the given resource.
`static void`	`cleanup(String name, String destDir)` Clear the cache for the given resource.
`private Pair<String,InputStream>`	`findZipEntryImpl(String extension, String namepart)`
`InputStream`	`findZipEntryInputStream(String extension, String namepart)` Like `findZipEntryPath(java.lang.String, java.lang.String)`, but returns the corresponding InputStream.
`String`	`findZipEntryPath(String extension, String namepart)` Looks for a certain entry inside a zip file and returns the entry path.
`CachedFile.CachingStrategy`	`getCachingStrategy()`
`String`	`getDestDir()`
`File`	`getFile()` Get local file for the requested resource.
`String`	`getHttpAccept()`
`InputStream`	`getInputStream()` Get InputStream to the requested resource.
`long`	`getMaxAge()`
`String`	`getName()`
`private static String`	`getPrefKey(URL url, String destDir)` Get preference key to store the location and age of the cached file.
`CachedFile`	`setCachingStrategy(CachedFile.CachingStrategy cachingStrategy)` Set the caching strategy.
`CachedFile`	`setDestDir(String destDir)` Set the destination directory for the cache file.
`CachedFile`	`setHttpAccept(String httpAccept)` Set the accepted MIME types sent in the HTTP Accept header.
`CachedFile`	`setHttpHeaders(Map<String,String> headers)` Sets the http headers.
`CachedFile`	`setMaxAge(long maxAge)` Set maximum age of cache file.
`CachedFile`	`setName(String name)` Set the name of the resource.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - name
```
protected String name
```
  - maxAge
```
protected long maxAge
```
  - destDir
```
protected String destDir
```
  - httpAccept
```
protected String httpAccept
```
  - cachingStrategy
```
protected CachedFile.CachingStrategy cachingStrategy
```
  - cacheFile
```
protected File cacheFile
```
  - initialized
```
protected boolean initialized
```
  - DEFAULT_MAXTIME
```
public static final long DEFAULT_MAXTIME
```
    See Also:
    
    Constant Field Values
  - DAYS
```
public static final long DAYS
```
    See Also:
    
    Constant Field Values
  - httpHeaders
```
private final Map<String,String> httpHeaders
```
- Constructor Detail
  - CachedFile
```
public CachedFile(String name)
```
    Constructs a CachedFile object from a given filename, URL or internal resource.
    Parameters:
    name - can be:
    
    relative or absolute file name
    
    file:///SOME/FILE the same as above
    
    http://... a URL. It will be cached on disk.
    
    resource://SOME/FILE file from the classpath (usually in the current *.jar)
    
    josmdir://SOME/FILE file inside josm user data directory (since r7058)
    
    josmplugindir://SOME/FILE file inside josm plugin directory (since r7834)
- Method Detail
  - setName
```
public CachedFile setName(String name)
```
    Set the name of the resource.
    Parameters:
    name - can be:
    
    relative or absolute file name
    
    file:///SOME/FILE the same as above
    
    http://... a URL. It will be cached on disk.
    
    resource://SOME/FILE file from the classpath (usually in the current *.jar)
    
    josmdir://SOME/FILE file inside josm user data directory (since r7058)
    
    josmplugindir://SOME/FILE file inside josm plugin directory (since r7834)
    Returns:
    
    this object
  - setMaxAge
```
public CachedFile setMaxAge(long maxAge)
```
    Set maximum age of cache file. Only applies to URLs. When this time has passed after the last download of the file, the cache is considered stale and a new download will be attempted.
    
    Parameters:
    
    maxAge - the maximum cache age in seconds
    
    Returns:
    
    this object
  - setDestDir
```
public CachedFile setDestDir(String destDir)
```
    Set the destination directory for the cache file. Only applies to URLs.
    
    Parameters:
    
    destDir - the destination directory
    
    Returns:
    
    this object
  - setHttpAccept
```
public CachedFile setHttpAccept(String httpAccept)
```
    Set the accepted MIME types sent in the HTTP Accept header. Only applies to URLs.
    
    Parameters:
    
    httpAccept - the accepted MIME types
    
    Returns:
    
    this object
  - setCachingStrategy
```
public CachedFile setCachingStrategy(CachedFile.CachingStrategy cachingStrategy)
```
    Set the caching strategy. Only applies to URLs.
    
    Parameters:
    
    cachingStrategy - caching strategy
    
    Returns:
    
    this object
  - setHttpHeaders
```
public CachedFile setHttpHeaders(Map<String,String> headers)
```
    Sets the http headers. Only applies to URL pointing to http or https resources
    
    Parameters:
    
    headers - that should be sent together with request
    
    Returns:
    
    this object
  - getName
```
public String getName()
```
  - getMaxAge
```
public long getMaxAge()
```
  - getDestDir
```
public String getDestDir()
```
  - getHttpAccept
```
public String getHttpAccept()
```
  - getCachingStrategy
```
public CachedFile.CachingStrategy getCachingStrategy()
```
  - getInputStream
```
public InputStream getInputStream()
                           throws IOException
```
    Get InputStream to the requested resource.
    
    Returns:
    
    the InputStream
    
    Throws:
    
    IOException - when the resource with the given name could not be retrieved
  - getFile
```
public File getFile()
             throws IOException
```
    Get local file for the requested resource.
    
    Returns:
    
    The local cache file for URLs. If the resource is a local file, returns just that file.
    
    Throws:
    
    IOException - when the resource with the given name could not be retrieved
  - findZipEntryPath
```
public String findZipEntryPath(String extension,
                               String namepart)
```
    Looks for a certain entry inside a zip file and returns the entry path. Replies a file in the top level directory of the ZIP file which has an extension extension. If more than one files have this extension, the last file whose name includes namepart is opened.
    
    Parameters:
    
    extension - the extension of the file we're looking for
    
    namepart - the name part
    
    Returns:
    
    The zip entry path of the matching file. Null if this cached file doesn't represent a zip file or if there was no matching file in the ZIP file.
  - findZipEntryInputStream
```
public InputStream findZipEntryInputStream(String extension,
                                           String namepart)
```
    Like findZipEntryPath(java.lang.String, java.lang.String), but returns the corresponding InputStream.
    
    Parameters:
    
    extension - the extension of the file we're looking for
    
    namepart - the name part
    
    Returns:
    
    InputStream to the matching file. Null if this cached file doesn't represent a zip file or if there was no matching file in the ZIP file.
    
    Since:
    
    6148
  - findZipEntryImpl
```
private Pair<String,InputStream> findZipEntryImpl(String extension,
                                                  String namepart)
```
  - cleanup
```
public static void cleanup(String name)
```
    Clear the cache for the given resource. This forces a fresh download.
    
    Parameters:
    
    name - the URL
  - cleanup
```
public static void cleanup(String name,
                           String destDir)
```
    Clear the cache for the given resource. This forces a fresh download.
    
    Parameters:
    
    name - the URL
    
    destDir - the destination directory (see setDestDir(java.lang.String))
  - getPrefKey
```
private static String getPrefKey(URL url,
                                 String destDir)
```
    Get preference key to store the location and age of the cached file. 2 resources that point to the same url, but that are to be stored in different directories will not share a cache file.
    
    Parameters:
    
    url - URL
    
    destDir - destination directory
    
    Returns:
    
    Preference key
  - checkLocal
```
private File checkLocal(URL url)
                 throws IOException
```
    Throws:
    
    IOException
  - checkOfflineAccess
```
private static void checkOfflineAccess(String urlString)
```

Class CachedFile

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

name

maxAge

destDir

httpAccept

cachingStrategy

cacheFile

initialized

DEFAULT_MAXTIME

DAYS

httpHeaders

Constructor Detail

CachedFile

Method Detail

setName

setMaxAge

setDestDir

setHttpAccept

setCachingStrategy

setHttpHeaders

getName

getMaxAge

getDestDir

getHttpAccept

getCachingStrategy

getInputStream

getFile

findZipEntryPath

findZipEntryInputStream

findZipEntryImpl

cleanup

cleanup

getPrefKey

checkLocal

checkOfflineAccess