CLASSES

Method Modifiers

8.4.3

Such inlining cannot be done at compile time unless it can be guaranteed that

Test

 and

Point

 will always be recompiled together, so that whenever

Point

and specifically its

move

 method changes, the code for

Test.main

 will also be

updated.

8.4.3.4

native

Methods

A method that is

native

 is implemented in platform dependent code, typically

written in another programming language such as C, C++,

FORTRAN

, or assembly

language. The body of a

native

 method is given as a semicolon only, indicating

that the implementation is omitted, instead of a block.

A compile time error occurs if a

native

 method is declared

abstract

.

For example, the class

RandomAccessFile

 of the standard package

java.io

might declare the following

native

 methods:

package java.io;

public class RandomAccessFile

implements DataOutput, DataInput

{

. . .

public native void open(String name, boolean writeable)

throws IOException;

public native int readBytes(byte[] b, int off, int len)

throws IOException;

public native void writeBytes(byte[] b, int off, int len)

throws IOException;

public native long getFilePointer() throws IOException;

public native void seek(long pos) throws IOException;

public native long length() throws IOException;

public native void close() throws IOException;

}

8.4.3.5

synchronized

Methods

A

synchronized

 method acquires a lock ( 17.1) before it executes. For a class

(

static)

 method, the lock associated with the

Class

 object ( 20.3) for the

method's class is used. For an instance method, the lock associated with

this

 (the

object for which the method was invoked) is used. These are the same locks that

can be used by the

synchronized

 statement ( 14.17); thus, the code:

class Test {

int count;

synchronized void bump() { count++; }

static int classCount;

static synchronized void classBump() {

classCount++;

}

}

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