THE PACKAGE JAVA.LANG

java.lang.ClassLoader

20.14

20.14.2

protected abstract Class loadClass(String name,

boolean link)

throws ClassNotFoundException

Every subclass of

ClassLoader

 that is not itself abstract must provide an imple 

mentation of the method

loadClass

.

The general contract of

loadClass

 is that, given the

name

 of a class, it either

returns the

Class

 object for the class or throws a

ClassNotFoundException

.

If a

Class

 object is to be returned and

link

 is

true

, then the

Class

 object

should be linked ( 12.3,  20.14.4) before it is returned.

In most cases, it is wise for a subclass of

ClassLoader

 ( 20.14) to implement

the

loadClass

 method as a

synchronized

 method.

20.14.3

protected final Class defineClass(byte data[],

int offset, int length)

throws NullPointerException,

IndexOutOfBoundsException, ClassFormatError

This method may be used by a class loader to define a new class.

The bytes in the array

data

 in positions

offset

 through

offset+length 1

should have the format of a valid class file as defined by the

Java Virtual Machine

Specification

.

If

data

 is

null

, then a

NullPointerException

 is thrown.

An

IndexOutOfBoundsException

 is thrown if any of the following are true:

offset

 is negative

length

 is negative

offset+length

 is greater than

data.length

If the indicated bytes of

data

 do not constitute a valid class definition, then a

ClassFormatError

 is thrown. Otherwise, this method creates and returns a

Class

 object as described by the data bytes

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