12.1.4

Invoke

Test.main

EXECUTION

12.1.4   Invoke

Test.main

Finally, after completion of the initialization for class

Test

 (during which other

consequential loading, linking, and initializing may have occurred), the method

main

 of

Test

 is invoked.

The method

main

 must be declared

public

,

static

, and

void

. It must accept

a single argument that is an array of strings.

12.2   Loading of Classes and Interfaces

Loading

 refers to the process of finding the binary form of a class or interface type

with a particular name, perhaps by computing it on the fly, but more typically by

retrieving a binary representation previously computed from source code by a

compiler, and constructing, from that binary form, a

Class

 object to represent the

class or interface.

The binary format of a class or interface is normally the

class

 file format

described in

The Java Virtual Machine

, but other formats are possible, provided

they meet the requirements specified in  13.1. The method

defineClass

( 20.14.3) of class

ClassLoader

 may be used to construct

Class

 objects from

binary representations in the

class

 file format.

A Java Virtual Machine system should maintain an internal table of classes

and interfaces that have been loaded for the sake of resolving symbolic references.

Each entry in the table should consist of a fully qualified class name (as a string),

a class loader, and a

Class

 object. Whenever a symbolic reference to a class or

interface is to be resolved, a class loader is identified that is responsible for load 

ing the class or interface, if necessary. The table should be consulted first, how 

ever; if it already contains an entry for that class name and class loader, then the

class object in that entry should be used and no method of the class loader should

be invoked. If the table contains no such entry, then the method

loadClass

( 20.14.2) of the class loader should be invoked, giving it the name of the class or

interface. If and when it returns, the class object that it returns should be used to

make a new entry in the table for that class name and class loader.

The purpose of this internal table is to allow the verification process ( 12.3.1)

to assume, for its purposes, that two classes or interfaces are the same if they have

the same name and the same class loader. This property allows a class to be veri 

fied without loading all the classes and interfaces that it uses, whether actively or

passively. Well behaved class loaders do maintain this property: given the same

name twice, a good class loader should return the same class object each time. But

without the internal table, a malicious class loader could violate this property and

undermine the security of the Java type system. A basic principle of the design of

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