OpenJDK 27 · java.lang.classfile.ClassFileVersion · APIdia, the JavaDoc alternative

Models the minor and major version numbers of a class file (JVMS 4.1). The class file version appears exactly once in each class, and is set to an unspecified default value if not explicitly provided.

The major versions of class file format begins at 45 for Java Platform version 1.0.2, and is continuous up to ClassFile#latestMajorVersion(). In general, each major version defines a new supported class file format, modeled by ClassFileFormatVersion, and supports all previous formats.

For major versions up to 55 for Java SE Platform 11, the minor version of any value is supported. For major versions 56 for Java SE Platform version 12 and above, the minor version must be 0 or 65535. The minor version 0 is always supported, and represents the format modeled by ClassFileFormatVersion. The minor version 65535 indicates the class file uses preview features of the Java SE Platform release represented by the major version. A Java Virtual Machine can only load such a class file if it has the same Java SE Platform version and the JVM has preview features enabled.

Method Summary

Modifier and Type	Method and Description
public int	Returns: the major version majorVersion() Returns the major version.
public int	Returns: the minor version minorVersion() Returns the minor version.
public static ClassFileVersion	Returns: a `ClassFileVersion` element of(int the major version majorVersion, int the minor version minorVersion) Returns a `ClassFileVersion` element.

Method Detail

majorVersion back to summary

majorVersion	back to summary
public int majorVersion() Returns the major version. It is a `u2` value. API Note Constants in `ClassFile` named `Java_#_VERSION`, where # is a release number, such as `ClassFile#JAVA_21_VERSION`, describe the class major versions of the Java Platform SE. Returns:int the major version

public int majorVersion()

Returns the major version. It is a u2 value.

API Note

Constants in ClassFile named Java_#_VERSION, where # is a release number, such as ClassFile#JAVA_21_VERSION, describe the class major versions of the Java Platform SE.

Returns:int: the major version

minorVersion back to summary

minorVersion	back to summary
public int minorVersion() Returns the minor version. It is a `u2` value. Returns:int the minor version

public int minorVersion()

Returns the minor version. It is a u2 value.

Returns:int: the minor version

of back to summary

of	back to summary
public static ClassFileVersion of(int majorVersion, int minorVersion) Returns a `ClassFileVersion` element. The minor version number may be `-1` to represent 65535. Parameters majorVersion:int the major version minorVersion:int the minor version Returns:ClassFileVersion a `ClassFileVersion` element Exceptions IllegalArgumentException: if the major version or the minor version is not `u2`; the minor version may be `-1`

public static ClassFileVersion of(int majorVersion, int minorVersion)

Returns a ClassFileVersion element. The minor version number may be -1 to represent 65535.

Parameters

majorVersion:int: the major version
minorVersion:int: the minor version

Returns:ClassFileVersion

a ClassFileVersion element

Exceptions

IllegalArgumentException:: if the major version or the minor version is not u2; the minor version may be -1

public sealed Interface ClassFileVersion

Method Summary

Method Detail