Package org.apache.tools.ant.types.selectors.modifiedselector

# Class ChecksumAlgorithm

java.lang.Object
org.apache.tools.ant.types.selectors.modifiedselector.ChecksumAlgorithm

All Implemented Interfaces:
  `Algorithm`

public class ChecksumAlgorithm extends Object implements Algorithm
Computes a 'checksum' for the content of file using java.util.zip.CRC32 and java.util.zip.Adler32. Use of this algorithm doesn't require any additional nested <param>s. Supported <param>s are:

Checksum algorithm parameters
name | values | description | required
--- | --- | --- | ---
algorithm.algorithm | ADLER | CRC (default) | name of the algorithm the checksum should use | no, defaults to CRC

Since:
  Ant 1.7
Version:
  2004-06-17

## Constructor Summary

Constructors
Constructor
Description
`ChecksumAlgorithm()`

## Method Summary

Modifier and Type
Method
Description
`String`
`getValue(File file)`
Computes a value for a file content with the specified checksum algorithm.
`void`
`initChecksum()`
Initialize the checksum interface.
`boolean`
`isValid()`
This algorithm supports only CRC and Adler.
`void`
`setAlgorithm(String algorithm)`
Specifies the algorithm to be used to compute the checksum.
`String`
`toString()`
Override Object.toString().

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

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

## Constructor Details

### ChecksumAlgorithm

public ChecksumAlgorithm()

## Method Details

### setAlgorithm

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

Parameters:
  `algorithm` - the digest algorithm to use

### initChecksum

public void initChecksum()
Initialize the checksum interface.

### isValid

public boolean isValid()
This algorithm supports only CRC and Adler.

Specified by:
  `isValid` in interface `Algorithm`
Returns:
  true if all is ok, otherwise false.

### getValue

public String getValue(File file)
Computes a value for a file content with the specified checksum algorithm.

Specified by:
  `getValue` in interface `Algorithm`
Parameters:
  `file` - File object for which the value should be evaluated.
Returns:
  The value for that file

### toString

public String toString()
Override Object.toString().

Overrides:
  `toString` in class `Object`
Returns:
  some information about this algorithm.