About the loading constraint

4 Message(s) by 2 Author(s) originally posted in harmony developer java

From: Xiaobing Wong

Date: Friday, December 14, 2007

------=_Part_441_24854211.1197627042528

Content-Disposition: inline

Loading constraint

<programming, mathematics> A {Boolean} {relation}, often an
	equality or {ineqality} relation, between the values of one or
	more mathematical variables (often two).  E.g. x>3 is a
	constraint on x.  {constraint satisfaction} attempts to assign
	values to variables so that all constraints are true.

	{Usenet} newsgroup: {news:comp.constraints}.  {FAQ
	(http://www.cs.unh.edu/ccc/archive/)}.

	(2002-06-08)

is a new regulation since sun jdk 1.2.I use a test suit,
finding that there are some difference between harmony and sun jdk 1.5 about
the load

1. To copy {data} (often {program} {code} to be {run}) into
	{memory}, possibly {parsing} it somehow in the process.
	E.g. "{WordPerfect} can't load this {RTF} file - are you sure
	it didn't get corrupted in the {download}?"  Opposite of
	{save}.

	2. The degree to which a computer, {network}, or other
	resource is used, sometimes expressed as a percentage of the
	maximum available.  E.g. "What kind of CPU load does that
	program give?", "The network's constantly running at 100%
	load".  Sometimes used, by extension, to mean "to increase the
	level of use of a resource".  E.g. "Loading a spreadsheet
	really loads the CPU".  See also: {load balancing}.

	3. To {install} a piece of {software} onto a system.
	E.g. "The computer guy is gonna come load Excel on my laptop
	for me".  This usage is widely considered to be incorrect.

	(2002-07-02)

ing constraint. And I am not quite sure about the native resolution
of harmony. Who can help me to explain why???
There are two Spoofed.class

1. <programming> The prototype for an {object} in an
	{object-oriented language}; analogous to a {derived type} in a
	{procedural language}.  A class may also be considered to be a
	set of objects which share a common structure and behaviour.
	The structure of a class is determined by the {class
	variables} which represent the {state} of an object of that
	class and the behaviour is given by a set of {methods}
	associated with the class.

	Classes are related in a {class hierarchy}.  One class may be
	a specialisation (a "{subclass}") of another (one of its
	"{superclasses}") or it may be composed of other classes or it
	may use other classes in a {client-server} relationship.  A
	class may be an {abstract class} or a {concrete class}.

	See also {signature}.

	2. <programming> See {type class}.

	3. <networking> One of three types of {Internet addresses}
	distinguished by their most significant bits.

	3. <language> A language developed by the {Andrew Project}.
	It was one of the first attempts to add {object-oriented}
	features to {C}.

	(1995-05-01)

. One is under the current

<electronics> The quantity of {charge} per unit time, measured
	in Amperes (Amps, A).  By historical convention, the sign of
	current is positive for currents flowing from positive to
	negative {potential}, but experience indicates that electrons
	are negatively charged and flow in the opposite direction.

	(1995-10-05)

direction, the other
is under the direction : greeters/ . They are different but with the same
name.

Spoofed.class

public class Spoofed {

private int

1. <programming> A common name for the {integer} data type.
	In {C} for example, it means a (signed) integer of the
	computer's native {word length}.

	2. <networking> The {top-level domain} for international
	organisations.

	(1999-01-26)

secretValue = 42;

public int giveMeFive() {

return 5;

}

static {

System.out.println(

"linking/ex8/Spoofed initialized.");

}

}

greeters/Spoofed.class

public class Spoofed {

private int secretValue = 100;

public int giveMeFive() {

return secretValue;

}

static {

System.out.println(

"linking/ex8/greeters/Spoofed initialized.");

}

}
The method

<programming> The name given in {Smalltalk} and other
	{object-oriented languages} to a procedure or routine
	associated with one or more {classes}.  An {object} of a
	certain class knows how to perform actions, e.g. printing
	itself or creating a new instance of itself, rather than the
	function (e.g. printing) knowing how to handle different types
	of object.

	Different classes may define methods with the same name
	(i.e. methods may be {polymorphic}).  The term "method" is used
	both for a named operation, e.g. "PRINT" and also for the code
	which a specific class provides to perform tha
	t operation.

	Most methods operate on objects that are instances of a
	certain class.  Some object-oriented languages call these
	"object methods" to distinguish then from "{class methods}".

	In {Smalltalk}, a method is defined by giving its name,
	documentation, temporary local variables and a sequence of
	expressions separated by "."s.

	(2000-03-22)

to invoke loading is as followed:

public void greet() {

Spoofed spoofed = new Spoofed();

System.out.println("secret val = "+ spoofed.giveMeFive());

spoofed = Delegated.getSpoofed();

System.out.println("secret val = "+ spoofed.giveMeFive());

}

In which the Delegated.class:

public class Delegated {

public static Spoofed getSpoofed() {

return new Spoofed();

}

}
Then we define the classloader to load the Spoofed.class in greeters. The
main function

1. <mathematics> (Or "map", "mapping") If D and C are sets
	(the domain and codomain) then a function f from D to C,
	normally written "f : D -> C" is a subset of D x C such that:

	1. For each d in D there exists some c in C such that (d,c) is
	an element of f.  I.e. the function is defined for every
	element of D.

	2. For each d in D, c1 and c2 in C, if both (d,c1) and (d,c2)
	are elements of f then c1 = c2.  I.e. the function is uniquely
	defined for every element of D.

	See also {image}, {inverse}, {partial function}.

	2. <programming> Computing usage derives from the mathematical
	term but is much less strict.  In programming (except in
	{functional programming}), a function may return different
	values each time it is called with the same argument values
	and may have {side effects}.

	A {procedure} is a function which returns no value but has
	only {side-effects}.  The {C} language, for example, has no
	procedures, only functions.  {ANSI C} even defines a {type},
	{void}, for the result of a function that has no result.

	(1996-09-01)

invokes greet().Results show as follows:
Result In sun jdk 1.5:

D:\linking\ex8>JAVA Greet greeters Cracker

linking/ex8/greeters/Spoofed initialized.

secret val = 100

Exception in thread

1. See {multithreading}.

	2. See {threaded code}.

	3. {topic thread}.

	[{Jargon File}]

"main" JAVA.lang.LinkageError: Class Spoofed violates
loader

constraints

at JAVA.lang.ClassLoader.defineClass1(Native Method)

at JAVA.lang.ClassLoader.defineClass(Unknown Source)

at JAVA.security.SecureClassLoader.defineClass(Unknown Source)

at JAVA.net.URLClassLoader.defineClass(Unknown Source)

at JAVA.net.URLClassLoader.access$100(Unknown Source)

at JAVA.net.URLClassLoader$1.run(Unknown Source)

at JAVA.security.AccessController.doPrivileged(Native Method)

at JAVA.net.URLClassLoader.findClass(Unknown Source)

at JAVA.lang.ClassLoader.loadClass(Unknown Source)

at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)

at JAVA.lang.ClassLoader.loadClass(Unknown Source)

at JAVA.lang.ClassLoader.loadClassInternal(Unknown Source)

at Delegated.getSpoofed(Delegated.JAVA:7)

at Cracker.greet(Cracker.JAVA:13)

at Greet.main(Greet.JAVA:39)
Result In harmony:

littleice@xxxxxxxxxxx:/trunk/target/hdk/jdk/jre/bin$ ./JAVA Greet
greeters Cracker

linking/ex8/greeters/Spoofed initialized.

secret val = 100

linking/ex8/Spoofed initialized.

secret val = 5

littleice@xxxxxxxxxxx:/trunk/target/hdk/jdk/jre/bin$

------=_Part_441_24854211.1197627042528--

From: Pavel Pervov

Date: Friday, December 14, 2007

------=_Part_150_5281096.1197629770355

Content-Disposition: inline

Xiaobing,

this is interesting observation indeed and it certainly deserves JIRA.

Could you, please, file

<file system> An element of data storage in a {file system}.

	The history of computing is rich in varied kinds of files and
	{file systems}, whether ornate (e.g., {Macintosh file system}
	for a well-known case) or deficient (e.g., many simple
	pre-1980s file systems don't allow {directories}).

	However, the prototypical file has these characteristics:

	* It is a single sequence of bytes (but consider {Macintosh}
	{resource forks}).

	* It has a finite length, unlike, e.g. a {Unix} {device}.

	* It is stored in a {non-volatile storage} medium (but see
	{ramdrive}).

	* It exists (nominally) in a {directory}.

	* It has a name that it can be referred to by in file
	operations, possibly in combination with its {path}.

	Additionally, a file system may associate other information
	with a file, such as {permission} bits or other {file
	attributes}; timestamps for file creation, last revision, and
	last access; revision numbers (a` la VMS), and other kinds of
	{magic}.

	Compare: {document}.

	(1997-04-08)

a JIRA and provide the whole test case and citation
(or link) to the spec where this behaviour is defined?

wrote in message:

Loading constraint is a new regulation since sun jdk 1.2.I use a test
suit,
finding that there are some difference between harmony and sun jdk 1.5about
the loading constraint. And I am not quite sure about the native
resolution
of harmony. Who can help me to explain why???
There are two Spoofed.class. One is under the current direction, the other
is under the direction : greeters/ . They are different but with the same
name.
Spoofed.class
public class Spoofed {
private int secretValue = 42;
public int giveMeFive() {
return 5;
}
static {
System.out.println(
"linking/ex8/Spoofed initialized.");
}
}
greeters/Spoofed.class
public class Spoofed {
private int secretValue = 100;
public int giveMeFive() {
return secretValue;
}
static {
System.out.println(
"linking/ex8/greeters/Spoofed initialized.");
}
}
The method to invoke loading is as followed:
public void greet() {
Spoofed spoofed = new Spoofed();
System.out.println("secret val = "+ spoofed.giveMeFive());
spoofed = Delegated.getSpoofed();
System.out.println("secret val = "+ spoofed.giveMeFive());
}
In which the Delegated.class:
public class Delegated {
public static Spoofed getSpoofed() {
return new Spoofed();
}
}
Then we define the classloader to load the Spoofed.class in greeters. The
main function invokes greet().Results show as follows:
Result In sun jdk 1.5:
D:\linking\ex8>JAVA Greet greeters Cracker
linking/ex8/greeters/Spoofed initialized.
secret val = 100
Exception in thread "main" JAVA.lang.LinkageError: Class Spoofed violates
loader
constraints
at JAVA.lang.ClassLoader.defineClass1(Native Method)
at JAVA.lang.ClassLoader.defineClass(Unknown Source)
at JAVA.security.SecureClassLoader.defineClass(Unknown Source)
at JAVA.net.URLClassLoader.defineClass(Unknown Source)
at JAVA.net.URLClassLoader.access$100(Unknown Source)
at JAVA.net.URLClassLoader$1.run(Unknown Source)
at JAVA.security.AccessController.doPrivileged(Native Method)
at JAVA.net.URLClassLoader.findClass(Unknown Source)
at JAVA.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at JAVA.lang.ClassLoader.loadClass(Unknown Source)
at JAVA.lang.ClassLoader.loadClassInternal(Unknown Source)
at Delegated.getSpoofed(Delegated.JAVA:7)
at Cracker.greet(Cracker.JAVA:13)
at Greet.main(Greet.JAVA:39)
Result In harmony:
littleice@xxxxxxxxxxx:/trunk/target/hdk/jdk/jre/bin$ ./JAVA Greet
greeters Cracker
linking/ex8/greeters/Spoofed initialized.
secret val = 100
linking/ex8/Spoofed initialized.
secret val = 5
littleice@xxxxxxxxxxx:/trunk/target/hdk/jdk/jre/bin$

--
Pavel Pervov,
Intel Enterprise Solutions Software Division

------=_Part_150_5281096.1197629770355--

From: Xiaobing Wong

Date: Monday, December 17, 2007

------=_Part_7864_28409170.1197887562751

Content-Disposition: inline

ok~
wrote in message:

Xiaobing,
this is interesting observation indeed and it certainly deserves JIRA.
Could you, please, file a JIRA and provide the whole test case and
citation
(or link) to the spec where this behaviour is defined?
Thank you very much.
wrote in message:
>
> Loading constraint is a new regulation since sun jdk 1.2.I use a test
> suit,
> finding that there are some difference between harmony and sun jdk
1.5about
> the loading constraint. And I am not quite sure about the native
> resolution
> of harmony. Who can help me to explain why???
>
>
>
> There are two Spoofed.class. One is under the current direction, the
other
> is under the direction : greeters/ . They are different but with the
same
> name.
>
> Spoofed.class
>
> public class Spoofed {
>
> private int secretValue = 42;
>
> public int giveMeFive() {
>
> return 5;
>
> }
>
> static {
>
> System.out.println(
>
> "linking/ex8/Spoofed initialized.");
>
> }
>
> }
>
> greeters/Spoofed.class
>
> public class Spoofed {
>
> private int secretValue = 100;
>
> public int giveMeFive() {
>
> return secretValue;
>
> }
>
> static {
>
> System.out.println (
>
> "linking/ex8/greeters/Spoofed initialized.");
>
> }
>
> }
>
>
>
> The method to invoke loading is as followed:
>
> public void greet() {
>
> Spoofed spoofed = new Spoofed();
>
> System.out.println("secret val = "+ spoofed.giveMeFive());
>
> spoofed = Delegated.getSpoofed();
>
> System.out.println("secret val = "+ spoofed.giveMeFive());
>
> }
>
> In which the Delegated.class:
>
> public class Delegated {
>
> public static Spoofed getSpoofed() {
>
> return new Spoofed();
>
> }
>
> }
>
>
>
> Then we define the classloader to load the Spoofed.class in greeters.
The
> main function invokes greet().Results show as follows:
>
>
>
> Result In sun jdk 1.5:
>
> D:\linking\ex8>JAVA Greet greeters Cracker
>
> linking/ex8/greeters/Spoofed initialized.
>
> secret val = 100
>
> Exception in thread "main" JAVA.lang.LinkageError: Class Spoofed
violates
> loader
>
> constraints
>
> at JAVA.lang.ClassLoader.defineClass1(Native Method)
>
> at JAVA.lang.ClassLoader.defineClass (Unknown Source)
>
> at JAVA.security.SecureClassLoader.defineClass(Unknown Source)
>
> at JAVA.net.URLClassLoader.defineClass(Unknown Source)
>
> at JAVA.net.URLClassLoader.access$100 (Unknown Source)
>
> at JAVA.net.URLClassLoader$1.run(Unknown Source)
>
> at JAVA.security.AccessController.doPrivileged(Native Method)
>
> at JAVA.net.URLClassLoader.findClass (Unknown Source)
>
> at JAVA.lang.ClassLoader.loadClass(Unknown Source)
>
> at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
>
> at JAVA.lang.ClassLoader.loadClass (Unknown Source)
>
> at JAVA.lang.ClassLoader.loadClassInternal(Unknown Source)
>
> at Delegated.getSpoofed(Delegated.JAVA:7)
>
> at Cracker.greet(Cracker.JAVA:13)
>
> at Greet.main(Greet.JAVA:39)
>
>
>
> Result In harmony:
>
> littleice@xxxxxxxxxxx:/trunk/target/hdk/jdk/jre/bin$ ./JAVA Greet
> greeters Cracker
>
> linking/ex8/greeters/Spoofed initialized.
>
> secret val = 100
>
> linking/ex8/Spoofed initialized.
>
> secret val = 5
>
> littleice@xxxxxxxxxxx:/trunk/target/hdk/jdk/jre/bin$
>
--
Pavel Pervov,
Intel Enterprise Solutions Software Division

------=_Part_7864_28409170.1197887562751--

From: Pavel Pervov

Date: Monday, December 17, 2007

------=_Part_556_30892177.1197906695325

Content-Disposition: inline

Thanks. I will look into this.

wrote in message:

ok~
wrote in message:
> Xiaobing,
>
> this is interesting observation indeed and it certainly deserves JIRA.
>
> Could you, please, file a JIRA and provide the whole test case and
> citation
> (or link) to the spec where this behaviour is defined?
>
> Thank you very much.
>
>
wrote in message:
> >
> > Loading constraint is a new regulation since sun jdk 1.2.I use a test
> > suit,
> > finding that there are some difference between harmony and sun jdk
> 1.5about
> > the loading constraint. And I am not quite sure about the native
> > resolution
> > of harmony. Who can help me to explain why???
> >
> >
> >
> > There are two Spoofed.class. One is under the current direction, the
> other
> > is under the direction : greeters/ . They are different but with the
> same
> > name.
> >
> > Spoofed.class
> >
> > public class Spoofed {
> >
> > private int secretValue = 42;
> >
> > public int giveMeFive() {
> >
> > return 5;
> >
> > }
> >
> > static {
> >
> > System.out.println(
> >
> > "linking/ex8/Spoofed initialized.");
> >
> > }
> >
> > }
> >
> > greeters/Spoofed.class
> >
> > public class Spoofed {
> >
> > private int secretValue = 100;
> >
> > public int giveMeFive() {
> >
> > return secretValue;
> >
> > }
> >
> > static {
> >
> > System.out.println (
> >
> > "linking/ex8/greeters/Spoofed initialized.");
> >
> > }
> >
> > }
> >
> >
> >
> > The method to invoke loading is as followed:
> >
> > public void greet() {
> >
> > Spoofed spoofed = new Spoofed();
> >
> > System.out.println("secret val = "+ spoofed.giveMeFive());
> >
> > spoofed = Delegated.getSpoofed();
> >
> > System.out.println("secret val = "+ spoofed.giveMeFive());
> >
> > }
> >
> > In which the Delegated.class:
> >
> > public class Delegated {
> >
> > public static Spoofed getSpoofed() {
> >
> > return new Spoofed();
> >
> > }
> >
> > }
> >
> >
> >
> > Then we define the classloader to load the Spoofed.class in greeters.
> The
> > main function invokes greet().Results show as follows:
> >
> >
> >
> > Result In sun jdk 1.5:
> >
> > D:\linking\ex8>JAVA Greet greeters Cracker
> >
> > linking/ex8/greeters/Spoofed initialized.
> >
> > secret val = 100
> >
> > Exception in thread "main" JAVA.lang.LinkageError: Class Spoofed
> violates
> > loader
> >
> > constraints
> >
> > at JAVA.lang.ClassLoader.defineClass1(Native Method)
> >
> > at JAVA.lang.ClassLoader.defineClass (Unknown Source)
> >
> > at JAVA.security.SecureClassLoader.defineClass(Unknown Source)
> >
> > at JAVA.net.URLClassLoader.defineClass(Unknown Source)
> >
> > at JAVA.net.URLClassLoader.access$100 (Unknown Source)
> >
> > at JAVA.net.URLClassLoader$1.run(Unknown Source)
> >
> > at JAVA.security.AccessController.doPrivileged(Native Method)
> >
> > at JAVA.net.URLClassLoader.findClass (Unknown Source)
> >
> > at JAVA.lang.ClassLoader.loadClass(Unknown Source)
> >
> > at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
> >
> > at JAVA.lang.ClassLoader.loadClass (Unknown Source)
> >
> > at JAVA.lang.ClassLoader.loadClassInternal(Unknown Source)
> >
> > at Delegated.getSpoofed(Delegated.JAVA:7)
> >
> > at Cracker.greet(Cracker.JAVA:13)
> >
> > at Greet.main(Greet.JAVA:39)
> >
> >
> >
> > Result In harmony:
> >
> > littleice@xxxxxxxxxxx:/trunk/target/hdk/jdk/jre/bin$ ./JAVA
Greet
> > greeters Cracker
> >
> > linking/ex8/greeters/Spoofed initialized.
> >
> > secret val = 100
> >
> > linking/ex8/Spoofed initialized.
> >
> > secret val = 5
> >
> > littleice@xxxxxxxxxxx:/trunk/target/hdk/jdk/jre/bin$
> >
>
>
>
> --
> Pavel Pervov,
> Intel Enterprise Solutions Software Division
>
--

Pavel Pervov,
Intel Enterprise Solutions Software Division

------=_Part_556_30892177.1197906695325--

Next Message: [testing] M4 candidate (r603534) testing status.

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