Uses of Class java.lang.ClassFormatError (Java Platform SE 8 )
Date: 2026-01-21

## Uses of Class
java.lang.ClassFormatError

- Packages that use ClassFormatError
  Package | Description
  --- | ---
  java.lang | Provides classes that are fundamental to the design of the Java programming language.
  java.lang.reflect | Provides classes and interfaces for obtaining reflective information about classes and objects.

- - ### Uses of ClassFormatError in java.lang

    Subclasses of ClassFormatError in java.lang
    Modifier and Type | Class and Description
    --- | ---
    `class` | `UnsupportedClassVersionError` Thrown when the Java Virtual Machine attempts to read a class file and determines that the major and minor version numbers in the file are not supported.

    Methods in java.lang that throw ClassFormatError
    Modifier and Type | Method and Description
    --- | ---
    `protected Class<?>` | ClassLoader.`defineClass(byte[] b, int off, int len)` Deprecated. Replaced by `defineClass(String, byte[], int, int)`
    `protected Class<?>` | ClassLoader.`defineClass(String name, byte[] b, int off, int len)` Converts an array of bytes into an instance of class `Class`.
    `protected Class<?>` | ClassLoader.`defineClass(String name, byte[] b, int off, int len, ProtectionDomain protectionDomain)` Converts an array of bytes into an instance of class `Class`, with an optional `ProtectionDomain`.
    `protected Class<?>` | ClassLoader.`defineClass(String name, ByteBuffer b, ProtectionDomain protectionDomain)` Converts a ``ByteBuffer`` into an instance of class `Class`, with an optional `ProtectionDomain`.

  - ### Uses of ClassFormatError in java.lang.reflect

    Subclasses of ClassFormatError in java.lang.reflect
    Modifier and Type | Class and Description
    --- | ---
    `class` | `GenericSignatureFormatError` Thrown when a syntactically malformed signature attribute is encountered by a reflective method that needs to interpret the generic signature information for a type, method or constructor.

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