Module org.freedesktop.cairo

Package org.freedesktop.cairo

Class Cairo

java.lang.Object

org.freedesktop.cairo.Cairo

public final class Cairo
extends Object

This class contains global declarations that do not belong in a specific cairo class definition.

Method Summary

Modifier and Type	Method	Description
static void	ensureInitialized()	Ensures the class initializer has loaded the cairo library.
static int	version()	Returns the version of the cairo library encoded in a single integer.
static int	versionEncode(int major, int minor, int micro)	encodes the given cairo version into an integer.
static String	versionString()	Returns the version of the cairo library as a human-readable string of the form "X.Y.Z".
static String	versionStringize(int major, int minor, int micro)	Encodes the given cairo version into a string.

Methods inherited from class java.lang.Object

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

Method Details

ensureInitialized

public static void ensureInitialized()

Ensures the class initializer has loaded the cairo library.

versionEncode

public static int versionEncode(int major,
 int minor,
 int micro)

encodes the given cairo version into an integer. The numbers returned by version() are encoded in the same way. Two encoded version numbers can be compared as integers. The encoding ensures that later versions compare greater than earlier versions.

Parameters:

major - the major component of the version number

minor - the minor component of the version number

micro - the micro component of the version number

Returns:

the encoded version.

Since:

1.0

versionStringize

public static String versionStringize(int major,
 int minor,
 int micro)

Encodes the given cairo version into a string. The numbers returned by versionString() are encoded in the same way.

Parameters:

major - the major component of the version number

minor - the minor component of the version number

micro - the micro component of the version number

Returns:

a string literal containing the version.

Since:

1.8

version

public static int version()

Returns the version of the cairo library encoded in a single integer. The encoding ensures that later versions compare greater than earlier versions.

A run-time comparison to check that cairo's version is greater than or equal to version X.Y.Z could be performed as follows:

 if (Cairo.version() >= versionEncode(X,Y,Z)) {...}
 

Returns:

the encoded version.

Since:

1.0

See Also:

• versionString()

versionString

public static String versionString()

Returns the version of the cairo library as a human-readable string of the form "X.Y.Z".

Cairo has a three-part version number scheme. In this scheme, we use even vs. odd numbers to distinguish fixed points in the software vs. in-progress development, (such as from git instead of a tar file, or as a "snapshot" tar file as opposed to a "release" tar file).

         _____ Major. Always 1, until we invent a new scheme.
        /  ___ Minor. Even/Odd = Release/Snapshot (tar files) or Branch/Head (git)
        | /  _ Micro. Even/Odd = Tar-file/git
        | | /
        1.0.0
 

Here are a few examples of versions that one might see.

        Releases
        --------
        1.0.0 - A major release
        1.0.2 - A subsequent maintenance release
        1.2.0 - Another major release
         
        Snapshots
        ---------
        1.1.2 - A snapshot (working toward the 1.2.0 release)
         
        In-progress development (eg. from git)
        --------------------------------------
        1.0.1 - Development on a maintenance branch (toward 1.0.2 release)
        1.1.1 - Development on head (toward 1.1.2 snapshot and 1.2.0 release)
 

Compatibility

The API/ABI compatibility guarantees for various versions are as follows. First, let's assume some cairo-using application code that is successfully using the API/ABI "from" one version of cairo. Then let's ask the question whether this same code can be moved "to" the API/ABI of another version of cairo. Moving from a release to any later version (release, snapshot, development) is always guaranteed to provide compatibility. Moving from a snapshot to any later version is not guaranteed to provide compatibility, since snapshots may introduce new API that ends up being removed before the next release. Moving from an in-development version (odd micro component) to any later version is not guaranteed to provide compatibility. In fact, there's not even a guarantee that the code will even continue to work with the same in-development version number. This is because these numbers don't correspond to any fixed state of the software, but rather the many states between snapshots and releases.

Returns:

a string containing the version.

Since:

1.0