votorola.a.diff

Class DiffCache

java.lang.Object

java.io.File

DiffCache

All Implemented Interfaces:

Serializable, Comparable<File>

@ThreadSafe
public final class DiffCache
extends File

A directory of cached diff output ~/votorola/in/diff. Cache files are created with broad permissions for writing by all (vote-server account, Tomcat and other process owners). Administrators should avoid deleting files at runtime, or temporary process errors may occur.

See Also:

en.wikipedia.org/wiki/Diff, www.gnu.org/software/diffutils/manual/diff.html, Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static LineTransformer1	LINE_TRANSFORMER The line transformer (LT) for the diffs of this wiki cache.
static Pattern	NO_DIFF_PATTERN The pattern of a negative 'diff' result, where the two files are identical.

Fields inherited from class java.io.File

pathSeparator, pathSeparatorChar, separator, separatorChar

Constructor Summary

Constructors

Constructor and Description
DiffCache(VoteServer _vS, VoteServer.ConstructionContext cc) Constructs a DiffCache for inclusion in a vote-server.

Method Summary

Methods

Modifier and Type	Method and Description
File	diffFile(DraftPair pair) Returns the cached diff output for the specified draft pair.

Methods inherited from class java.io.File

canExecute, canRead, canWrite, compareTo, createNewFile, createTempFile, createTempFile, delete, deleteOnExit, equals, exists, getAbsoluteFile, getAbsolutePath, getCanonicalFile, getCanonicalPath, getFreeSpace, getName, getParent, getParentFile, getPath, getTotalSpace, getUsableSpace, hashCode, isAbsolute, isDirectory, isFile, isHidden, lastModified, length, list, list, listFiles, listFiles, listFiles, listRoots, mkdir, mkdirs, renameTo, setExecutable, setExecutable, setLastModified, setReadable, setReadable, setReadOnly, setWritable, setWritable, toPath, toString, toURI, toURL

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

LINE_TRANSFORMER

public static final LineTransformer1 LINE_TRANSFORMER

The line transformer (LT) for the diffs of this wiki cache. It partly determines the structure of each diff (D) and is equally tied to the diff identification scheme (ID-D-LT). ID maps a diff URL (and cache filename) to a D in a stable manner, such that a reader following a URL that was embedded in an archived discussion will see the same D as the original conversants. Any change of transformer (LT') that would substantially alter a diff (D') will therefore be deployed under a new identification scheme (ID').

NO_DIFF_PATTERN

public static final Pattern NO_DIFF_PATTERN

The pattern of a negative 'diff' result, where the two files are identical.

Constructor Detail

DiffCache

public DiffCache(VoteServer _vS,
         VoteServer.ConstructionContext cc)
          throws IOException

Constructs a DiffCache for inclusion in a vote-server.

Throws:

IOException

See Also:

VoteServer.diffCache()

Method Detail

diffFile

public File diffFile(DraftPair pair)
              throws IOException

Returns the cached diff output for the specified draft pair. If the output is not yet cached, then it is generated anew and cached for future calls.

Throws:

IOException