XPInstall API Reference:InstallVersion Object:Methods:compareTo

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Contents 1 compareTo 1.1 Method of 1.2 Syntax 1.3 Parameters 1.4 Returns 1.5 Example

[edit] compareTo

Compares the version information specified in this object to the version information specified in the version parameter.

[edit] Method of

InstallVersion object

[edit] Syntax

compareTo ( InstallVersion version);

compareTo ( String version);

compareTo ( int major, int minor, int release, int build);

[edit] Parameters

The compareTo method has the following parameters:

maj

The major version number.

min

Minor version number.

rev

Revision number.

bld

Build number.

version

An InstallVersion object or a String representing version information in the format "4.1.2.1234".

[edit] Returns

If the versions are the same, this method returns 0. If this version object represents a smaller (earlier) version than that represented by the version parameter, this method returns a negative number. Otherwise, it returns a positive number. In particular, this method returns one of the following values:

-4 

This version object has a smaller (earlier) major number than version.

-3 

This version object has a smaller (earlier) minor number than version.

-2 

This version object has a smaller (earlier) release number than version.

-1 

This version object has a smaller (earlier) build number than version.

0 

The version numbers are the same; both objects represent the same version.

1 

This version object has a larger (newer) build number than version.

2 

This version object has a larger (newer) release number than version.

3 

This version object has a larger (newer) minor number than version.

4 

This version object has a larger (newer) major number than version.

The following constants are defined and available for checking the value returned by compareTo:

InstallVersion.MAJOR_DIFF

InstallVersion.MINOR_DIFF

InstallVersion.REL_DIFF

InstallVersion.BLD_DIFF

InstallVersion.EQUAL

InstallVersion.MAJOR_DIFF_MINUS

InstallVersion.MINOR_DIFF_MINUS

InstallVersion.REL_DIFF_MINUS

InstallVersion.BLD_DIFF_MINUS

[edit] Example

This code uses the compareTo method to determine whether or not version 3.2.1 of the Royal Airways software has been previously installed:

existingVI = InstallTrigger.getVersion("/royalairways/royalsw");

if ( existingVI.compareTo("3.2.1") <= 0 ) {
   // ... proceed to update ...
   }