Package org.apache.tools.ant.taskdefs

# Class Checksum

java.lang.Object
org.apache.tools.ant.ProjectComponent
org.apache.tools.ant.Task
org.apache.tools.ant.taskdefs.MatchingTask
org.apache.tools.ant.taskdefs.Checksum

All Implemented Interfaces:
  `Cloneable`, `Condition`, `SelectorContainer`

public class Checksum extends MatchingTask implements Condition
Used to create or verify file checksums.

Since:
  Ant 1.5

## Nested Class Summary

Nested Classes
Modifier and Type
Class
Description
`static class`
`Checksum.FormatElement`
Helper class for the format attribute.

## Field Summary

### Fields inherited from class org.apache.tools.ant.taskdefs.MatchingTask

`fileset`

### Fields inherited from class org.apache.tools.ant.Task

`target, taskName, taskType, wrapper`

### Fields inherited from class org.apache.tools.ant.ProjectComponent

`description, location, project`

## Constructor Summary

Constructors
Constructor
Description
`Checksum()`

## Method Summary

Modifier and Type
Method
Description
`void`
`add(ResourceCollection rc)`
Add a resource collection.
`void`
`addFileset(FileSet set)`
Files to generate checksums for.
`static byte[]`
`decodeHex(char[] data)`
Converts an array of characters representing hexadecimal values into an array of bytes of those same values.
`boolean`
`eval()`
Calculate the checksum(s)
`void`
`execute()`
Calculate the checksum(s).
`void`
`setAlgorithm(String algorithm)`
Specifies the algorithm to be used to compute the checksum.
`void`
`setFile(File file)`
Sets the file for which the checksum is to be calculated.
`void`
`setFileext(String fileext)`
Sets the file extension that is be to used to create or identify destination file.
`void`
`setForceOverwrite(boolean forceOverwrite)`
Whether or not to overwrite existing file irrespective of whether it is newer than the source file.
`void`
`setFormat(Checksum.FormatElement e)`
Select the in/output pattern via a well know format name.
`void`
`setPattern(String pattern)`
Specify the pattern to use as a MessageFormat pattern.
`void`
`setProperty(String property)`
Sets the property to hold the generated checksum.
`void`
`setProvider(String provider)`
Sets the MessageDigest algorithm provider to be used to calculate the checksum.
`void`
`setReadBufferSize(int size)`
The size of the read buffer to use.
`void`
`setTodir(File todir)`
Sets the root directory where checksum files will be written/read
`void`
`setTotalproperty(String totalproperty)`
Sets the property to hold the generated total checksum for all files.
`void`
`setVerifyproperty(String verifyProperty)`
Sets the verify property.

### Methods inherited from class org.apache.tools.ant.taskdefs.MatchingTask

`add, addAnd, addContains, addContainsRegexp, addCustom, addDate, addDepend, addDepth, addDifferent, addFilename, addMajority, addModified, addNone, addNot, addOr, addPresent, addSelector, addSize, addType, appendSelector, createExclude, createExcludesFile, createInclude, createIncludesFile, createPatternSet, getDirectoryScanner, getImplicitFileSet, getSelectors, hasSelectors, selectorCount, selectorElements, setCaseSensitive, setDefaultexcludes, setExcludes, setExcludesfile, setFollowSymlinks, setIncludes, setIncludesfile, setProject, XsetIgnore, XsetItems`

### Methods inherited from class org.apache.tools.ant.Task

`bindToOwner, getOwningTarget, getRuntimeConfigurableWrapper, getTaskName, getTaskType, getWrapper, handleErrorFlush, handleErrorOutput, handleFlush, handleInput, handleOutput, init, isInvalid, log, log, log, log, maybeConfigure, perform, reconfigure, setOwningTarget, setRuntimeConfigurableWrapper, setTaskName, setTaskType`

### Methods inherited from class org.apache.tools.ant.ProjectComponent

`clone, getDescription, getLocation, getProject, setDescription, setLocation`

### Methods inherited from class java.lang.Object

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

## Constructor Details

### Checksum

public Checksum()

## Method Details

### setFile

public void setFile(File file)
Sets the file for which the checksum is to be calculated.

Parameters:
  `file` - a `File` value

### setTodir

public void setTodir(File todir)
Sets the root directory where checksum files will be written/read

Parameters:
  `todir` - the directory to write to
Since:
  Ant 1.6

### setAlgorithm

public void setAlgorithm(String algorithm)
Specifies the algorithm to be used to compute the checksum. Defaults to "MD5". Other popular algorithms like "SHA" may be used as well.

Parameters:
  `algorithm` - a `String` value

### setProvider

public void setProvider(String provider)
Sets the MessageDigest algorithm provider to be used to calculate the checksum.

Parameters:
  `provider` - a `String` value

### setFileext

public void setFileext(String fileext)
Sets the file extension that is be to used to create or identify destination file.

Parameters:
  `fileext` - a `String` value

### setProperty

public void setProperty(String property)
Sets the property to hold the generated checksum.

Parameters:
  `property` - a `String` value

### setTotalproperty

public void setTotalproperty(String totalproperty)
Sets the property to hold the generated total checksum for all files.

Parameters:
  `totalproperty` - a `String` value
Since:
  Ant 1.6

### setVerifyproperty

public void setVerifyproperty(String verifyProperty)
Sets the verify property. This project property holds the result of a checksum verification - "true" or "false"

Parameters:
  `verifyProperty` - a `String` value

### setForceOverwrite

public void setForceOverwrite(boolean forceOverwrite)
Whether or not to overwrite existing file irrespective of whether it is newer than the source file. Defaults to false.

Parameters:
  `forceOverwrite` - a `boolean` value

### setReadBufferSize

public void setReadBufferSize(int size)
The size of the read buffer to use.

Parameters:
  `size` - an `int` value

### setFormat

public void setFormat(Checksum.FormatElement e)
Select the in/output pattern via a well know format name.

Parameters:
  `e` - an `enumerated` value
Since:
  1.7.0

### setPattern

public void setPattern(String pattern)
Specify the pattern to use as a MessageFormat pattern.

{0} gets replaced by the checksum, {1} by the filename.

Parameters:
  `pattern` - a `String` value
Since:
  1.7.0

### addFileset

public void addFileset(FileSet set)
Files to generate checksums for.

Parameters:
  `set` - a fileset of files to generate checksums for.

### add

public void add(ResourceCollection rc)
Add a resource collection.

Parameters:
  `rc` - the ResourceCollection to add.

### execute

public void execute() throws BuildException
Calculate the checksum(s).

Overrides:
  `execute` in class `Task`
Throws:
  `BuildException` - on error

### eval

public boolean eval() throws BuildException
Calculate the checksum(s)

Specified by:
  `eval` in interface `Condition`
Returns:
  Returns true if the checksum verification test passed, false otherwise.
Throws:
  `BuildException` - on error

### decodeHex

public static byte[] decodeHex(char[] data) throws BuildException
Converts an array of characters representing hexadecimal values into an array of bytes of those same values. The returned array will be half the length of the passed array, as it takes two characters to represent any given byte. An exception is thrown if the passed char array has an odd number of elements. NOTE: This code is copied from jakarta-commons codec.

Parameters:
  `data` - an array of characters representing hexadecimal values
Returns:
  the converted array of bytes
Throws:
  `BuildException` - on error