BINARY COMPATIBILITY

Method and Constructor Overloading

13.4.22

the method is

private

 to its class

an entire package is guaranteed to be kept together and the method is accessi 

ble only within that package

a set of Java code is being compiled to a special binary format where the spec 

ified method is available only within a binary or set of binaries which are

being kept together.

The keyword

final

 on a method does not mean that the method can be safely

inlined; it only means that the method cannot be overridden. Unless the compiler

has extraordinary knowledge, it is still possible that a new version of that method

will be provided at link time.

In general we suggest that Java implementations use late bound (run time)

code generation and optimization.

13.4.22   Method and Constructor Overloading

Adding new methods that overload existing method names does not break com 

patibility with pre existing binaries. The method signature to be used for each

method invocation was determined when these existing binaries were compiled;

therefore newly added methods will not be used, even if their signatures are both

applicable and more specific than the method signature originally chosen.

While adding a new overloaded method or constructor may cause a compile 

time error the next time a class or interface is compiled because there is no

method or constructor that is most specific ( 15.11.2.2), no such error occurs

when a Java program is executed, because no overload resolution is done at execu 

tion time.

If the example program:

class Super {

static void out(float f) { System.out.println("float"); }

}

class Test {

public static void main(String[] args) {

Super.out(2);

}

}

is compiled and executed, it produces the output:

float

Suppose that a new version of class

Super

 is produced:

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