Bz2 Objective-C Reference Documentation
CkoBz2
Current Version: 11.1.0
Provides the ability to create and unzip .bz2 compressed files using the BZip2 compression algorithm.
Object Creation
CkoBz2 *obj = [[CkoBz2 alloc] init];
Properties
AbortCurrent
When set to YES, causes the currently running method to abort. Methods that always finish quickly (i.e.have no length file operations or network communications) are not affected. If no method is running, then this property is automatically reset to NO when the next method is called. When the abort occurs, this property is reset to NO. Both synchronous and asynchronous method calls can be aborted. (A synchronous method call could be aborted by setting this property from a separate thread.)
DebugLogFilePath
If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.
Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.
Possible causes of hangs include:
- A timeout property set to 0, indicating an infinite timeout.
- A hang occurring within an event callback in the application code.
- An internal bug in the Chilkat code causing the hang.
HeartbeatMs
The interval in milliseconds between each AbortCheck event callback, which enables an application to abort certain method calls before they complete. By default, HeartbeatMs is set to 0, meaning no AbortCheck event callbacks will trigger.
LastErrorHtml
Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastErrorText
Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
LastErrorXml
Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.
topLastMethodSuccess
Indicates the success or failure of the most recent method call: YES means success, NO means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages.
VerboseLogging
If set to YES, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is NO. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.
Version
Methods
CompressBd
BZ2 compress the contents of bd. After compression, the bd contains the binary content of a .bz2 file, which is slightly different than simple BZIP2 compressed data because a .bz2 file contains:
- Header
- Compressed blocks
- End-of-stream trailer
Returns YES for success, NO for failure.
topCompressBdAsync (1)
Creates an asynchronous task to call the CompressBd method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
CompressFile
toPath:(NSString *)toPath;
Compresses a file to create a BZip2 compressed file (.bz2).
Note: Both inFilename and toPath should be relative or absolute file paths (not just a path to a directory). For example someDir1/someDir2/myFile.txt or c:/someDir1/myFile.bz2.
Returns YES for success, NO for failure.
CompressFileAsync (1)
Creates an asynchronous task to call the CompressFile method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
CompressFileToMem
CompressFileToMemAsync (1)
Creates an asynchronous task to call the CompressFileToMem method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
CompressMemory
CompressMemoryAsync (1)
Creates an asynchronous task to call the CompressMemory method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
CompressMemToFile
toPath:(NSString *)toPath;
BZip2 compresses and creates a .bz2 file from in-memory data.
Returns YES for success, NO for failure.
topCompressMemToFileAsync (1)
Creates an asynchronous task to call the CompressMemToFile method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
LoadTaskCaller
UncompressBd
BZ2 uncompress the contents of bd, which initially should contain the bytes of a .bz2 file. After uncompressing, the bd contains the original uncompressed content.
Returns YES for success, NO for failure.
topUncompressBdAsync (1)
Creates an asynchronous task to call the UncompressBd method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
UncompressFile
toPath:(NSString *)toPath;
UncompressFileAsync (1)
Creates an asynchronous task to call the UncompressFile method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
UncompressFileToMem
UncompressFileToMemAsync (1)
Creates an asynchronous task to call the UncompressFileToMem method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
UncompressMemory
UncompressMemoryAsync (1)
Creates an asynchronous task to call the UncompressMemory method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
UncompressMemToFile
toPath:(NSString *)toPath;
Unzips from an in-memory image of a .bz2 file to a file.
Returns YES for success, NO for failure.
topUncompressMemToFileAsync (1)
Creates an asynchronous task to call the UncompressMemToFile method with the arguments provided.
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
Events
To implement an event callback, your application would define and implement a class that inherits from CkoBaseProgress. Your application can implement methods to override some or all of the default/empty method implementations of the CkoBaseProgress base class.
For example:
CkoBz2 *bz = [[CkoBz2 alloc] init]; MyBz2Progress *callbackObj = [[MyBz2Progress alloc] init]; [bz setEventCallbackObject:callbackObj];
MyBz2Progress interface example:
#import "CkoBz2Progress.h"
@interface MyBz2Progress : CkoBaseProgress {
}
- (id)init;
- (void)dealloc;
- (void)dispose;
- (void)AbortCheck:(BOOL *)abort;
- (void)PercentDone:(NSNumber *)pctDone
abort:(BOOL *)abort;
- (void)ProgressInfo:(NSString *)name
value:(NSString *)value;
- (void)TaskCompleted:(CkoTask *)task;
@endAbortCheck
Enables a method call to be aborted by triggering the AbortCheck event at intervals defined by the HeartbeatMs property. If HeartbeatMs is set to its default value of 0, no events will occur. For instance, set HeartbeatMs to 200 to trigger 5 AbortCheck events per second.
PercentDone
abort:(BOOL *)abort;
This provides the percentage completion for any method involving network communications or time-consuming processing, assuming the progress can be measured as a percentage. This event is triggered only when it's possible and logical to express the operation's progress as a percentage. The pctDone argument will range from 1 to 100. For methods that finish quickly, the number of PercentDone callbacks may vary, but the final callback will have pctDone equal to 100. For longer operations, callbacks will not exceed one per percentage point (e.g., 1, 2, 3, ..., 98, 99, 100).
The PercentDone callback also acts as an AbortCheck event. For fast methods where PercentDone fires, an AbortCheck event may not trigger since the PercentDone callback already provides an opportunity to abort. For longer operations, where time between PercentDone callbacks is extended, AbortCheck callbacks enable more responsive operation termination.
To abort the operation, set the abort output argument to YES. This will cause the method to terminate and return a failure status or corresponding failure value.
ProgressInfo
value:(NSString *)value;
This event callback provides tag name/value pairs that detail what occurs during a method call. To discover existing tag names, create code to handle the event, emit the pairs, and review them. Most tag names are self-explanatory.
TaskCompleted
Called from the background thread when an asynchronous task completes.