JSObject.call(method, ARGS) with Safari

R

Richard Maher

Hi.

Has anyone been able to pass the ARGS parameter to JSObject's "call" method
*and* pass arguments via the "args" parameter? An example of your
work-around perhaps?

I'm having no trouble calling methods on all sorts of complex Javascript
objects but when it comes to passing the arguments array I keep getting
nullpointerexception :-(

Firefox, IE, Chrome, and Opera are all onboard and ok.

Cheers Richard Maher
 
R

Richard Maher

Richard Maher said:
Hi.

Has anyone been able to pass the ARGS parameter to JSObject's "call"
method *and* pass arguments via the "args" parameter? An example of your
work-around perhaps?

I'm having no trouble calling methods on all sorts of complex Javascript
objects but when it comes to passing the arguments array I keep getting
nullpointerexception :-(

Firefox, IE, Chrome, and Opera are all onboard and ok.

Cheers Richard Maher

Don't know if this is relevant: -

JSValueRef JSObjectCallAsFunction(JSContextRef ctx, JSObjectRef object,
JSObjectRef thisObject, size_t argumentCount, const JSValueRef arguments[],
JSValueRef* exception)
{


JSValueRef result = toRef(jsObject->call(exec, jsThisObject, argList));
// returns NULL if object->implementsCall() is false

.. . . and if so, how one specifies "implementsCall()" as "true"
 
L

Lew

Richard said:
Has anyone been able to pass the ARGS parameter to JSObject's "call"
method *and* pass arguments via the "args" parameter? An example of your
work-around perhaps?

I'm having no trouble calling methods on all sorts of complex Javascript
objects but when it comes to passing the arguments array I keep getting
nullpointerexception [sic] :-(

Maybe if you showed us any code, or better yet, an SSCCE, we could help.

All I can say at this point is that you're passing it wrong.
Don't know if this is relevant: -

JSValueRef JSObjectCallAsFunction(JSContextRef ctx, JSObjectRef object,
JSObjectRef thisObject, size_t argumentCount, const JSValueRef arguments[],
JSValueRef* exception)
{


JSValueRef result = toRef(jsObject->call(exec, jsThisObject, argList));
// returns NULL if object->implementsCall() is false

. . . and if so, how one specifies "implementsCall()" as "true"

That isn't Java code.
 
A

Arved Sandstrom

Richard said:
Has anyone been able to pass the ARGS parameter to JSObject's "call"
method *and* pass arguments via the "args" parameter? An example of your
work-around perhaps?

I'm having no trouble calling methods on all sorts of complex Javascript
objects but when it comes to passing the arguments array I keep getting
nullpointerexception [sic] :-(

Maybe if you showed us any code, or better yet, an SSCCE, we could help.

All I can say at this point is that you're passing it wrong.
Don't know if this is relevant: -

JSValueRef JSObjectCallAsFunction(JSContextRef ctx, JSObjectRef object,
JSObjectRef thisObject, size_t argumentCount, const JSValueRef
arguments[],
JSValueRef* exception)
{


JSValueRef result = toRef(jsObject->call(exec, jsThisObject,
argList));
// returns NULL if object->implementsCall() is false

. . . and if so, how one specifies "implementsCall()" as "true"

That isn't Java code.
True, it's not, it's JavascriptCore. So this is a multi-language problem
with both Java (netscape.javascript.JSObject) and JavaScript being
involved. I think we can handle that.

I spent a month earlier this year doing an integration for a customer in
an Oracle Forms environment that involved Java, Oracle Forms PL/SQL, and
some JavaScript. Much of last year was Java EE web apps where Java, XML,
XSLT, XHTML, CSS and SQL figured. Right now I am working ESB
integrations where Java is important but less than 50 percent.

Most of us spend quality time doing hybrid work. Sometimes a problem is
a one-language problem but often it's not. We can't get too picky about
what we'll look at and what we won't. As long as Java is involved to
some extent I think it's worth a first look.

I agree that an SSCCE is called for in any case.

AHS
 
R

Richard Maher

Arved Sandstrom said:
On 12-04-21 08:45 AM, Lew wrote:

I agree that an SSCCE is called for in any case.

Thanks for the replies. I'll cut it down to just the jsobject.call(m, ARGS)
test tomorrow, but for now: -

import java.applet.Applet;
import netscape.javascript.JSObject;
import netscape.javascript.JSException;

public class JavaJSTest extends Applet {

JSObject laundry;
Object rinseArgs[] = new Object[1];

public synchronized void init() {

System.out.println("Starting Tests. . .");

JSObject window = JSObject.getWindow(this);

final String createLaundry =
"(function(){" +
"function Laundry(){" +
"this.launder = function(JSObject){" +
"alert('In Laundry');" +
"return JSObject;}}" +
"return new Laundry();" +
"})();";

laundry = (JSObject)window.eval(createLaundry);

// Test function calls
String str = (String) window.eval("getString();");
if (!str.equals("Hello, world!")) {
throw new RuntimeException(); // test failed
}
Number num = (Number) window.eval("getNumber()");
if (num.intValue() != 5) {
throw new RuntimeException(); // test failed
}
// Test field access
JSObject res = (JSObject) window.eval("new cities();");
if (!((String) res.getMember("b")).equals("Belgrade")) {
throw new RuntimeException(); // test failed
}
res.setMember("b", "Belfast");
if (!res.getMember("b").equals("Belfast")) {
throw new RuntimeException(); // test failed
}
// Test CALL
Boolean ans = (Boolean)res.call("d", null);
System.out.println("ans is " + ans.booleanValue());

// Test CALL with param
rinseArgs[0] = new String("A param");
Boolean pans = (Boolean)res.call("e", rinseArgs);
System.out.println("param ans is " + pans.booleanValue());

// Test array access
res = (JSObject) window.eval("getTestArray();");
if (!((String) res.getSlot(0)).equals("foo") ||
!((String) res.getSlot(1)).equals("bar")) {
throw new RuntimeException(); // test failed
}
res.setSlot(1, "baz");
if (!((String) res.getSlot(1)).equals("baz")) {
throw new RuntimeException(); // test failed
}
res.setSlot(2, "qux"); // Define new array element
if (!((String) res.getSlot(2)).equals("qux")) {
throw new RuntimeException(); // test failed
}
res.removeMember("b");
try {
res.getMember("b");
// throw new RuntimeException(); // test failed
System.out.println("This browser does not support
removeMember"); // test failed
} catch (JSException e) {
// Member should not be present any more
}

System.out.println(". . .Tests complete");
}

public void hello() {
System.out.println("Hello");
}

public boolean testCall(JSObject blob) {
System.out.println("In method - testCall()");

JSObject cleanBuf;
boolean retVal = false;

try {
rinseArgs[0] = blob;
System.out.println("before launder");
try {
cleanBuf = (JSObject)laundry.call("launder", rinseArgs);
}
catch (Exception e) {
throw e;
}
System.out.println("after launder");
// System.out.println("ans is " + abc.booleanValue());

System.out.println("blob.call()");
Boolean resp = (Boolean)cleanBuf.call("e",null);
System.out.println("Setting retVal");
retVal = resp.booleanValue();
} catch (JSException ex) {
Exception ex2 = (Exception)ex.getWrappedException();
if(ex2 != null) {
System.out.println(ex2.getClass().getName() + " " +
ex2.getMessage());
} else {
System.out.println(ex.getClass().getName() + " " +
ex.getMessage());
}
} catch (Exception ex) {
System.out.println(ex.getClass().getName() + " " +
ex.getMessage());
}
return retVal;
}

}


And the HTML: _

<html>
<head>
<script language="javascript">
var app;

function load() {
var objectTag = "<object ";

if (/Internet Explorer/.test(navigator.appName)) {
objectTag = objectTag +
'classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93" ';
} else {
objectTag = objectTag +
'type="application/x-java-applet" ';
}

objectTag = objectTag +
'width= "0" height= "0" id="app">' +
'<param name="codebase" value="http://127.0.0.1">' +
'<param name="code" value="JavaJSTest">' +
'<param name="java_version" value="1.6+">' +
'<param name="mayscript" value="true">' +
'<param name="scriptable" value="true">' +
'</object>';

var appletDiv = document.createElement("div");
appletDiv.innerHTML = objectTag;

try {
document.body.appendChild(appletDiv);
chanG = document.getElementById("app");
}
catch(err) {
alert("Unable to append applet: -\n" +
(err.description||err.message));
chanG = null;
};

if (chanG == null) {
throw new Error("Was unable to initialize the applet");
};

var x = new cities();
var y = x.e();
alert("X = "+y);
}

// Return a string value to Java
function getString() {
return "Hello, world!";
}

function getNumber() {
return 5;
}

// Make an object with city names and an index letter.
function cities() {
var msg = "Good Bye";
this.a = "Athens";
this.b = "Belgrade";
this.c = "Cairo";
// this.e = function(){alert(msg); return true;};
// this.e = function(){if (window.console) {console.log("Message is "
+ msg)};return true;};
// this.e = function(){throw("A Wobbly");return true;};
}

cities.prototype = {
d : function(){alert("hello"); return true;}
,e : function(){alert("good-Bye"); return true;}
,f : function(param){alert("Param = " + param); return true;}
};

function getTestArray() {
return [ "foo", "bar" ];
}

function doIt() {
var list = new cities();
var reply = chanG.testCall(list);
alert("Reply = "+reply);
}

</script>
</head>
<body onload="load();">

STUFF

<input type="Button" id="btn1" value="HitMe" onclick="doIt();"/>

</body>
</html>

Thanks agin

Cheers Richard Maher
 
L

Lew

Arved said:
Lew said:
Richard said:
Has anyone been able to pass the ARGS parameter to JSObject's "call"
method *and* pass arguments via the "args" parameter? An example of your
work-around perhaps?

I'm having no trouble calling methods on all sorts of complex Javascript
objects but when it comes to passing the arguments array I keep getting
nullpointerexception [sic] :-(

Maybe if you showed us any code, or better yet, an SSCCE, we could help.

All I can say at this point is that you're passing it wrong.
Firefox, IE, Chrome, and Opera are all onboard and ok.
Don't know if this is relevant: -

Nor do we, and how the heck could we with the paucity of information you provided?
JSValueRef JSObjectCallAsFunction(JSContextRef ctx, JSObjectRef object,
JSObjectRef thisObject, size_t argumentCount, const JSValueRef
arguments[],
JSValueRef* exception)
{


JSValueRef result = toRef(jsObject->call(exec, jsThisObject,
argList));
// returns NULL if object->implementsCall() is false

. . . and if so, how one specifies "implementsCall()" as "true"

That isn't Java code.
True, it's not, it's JavascriptCore. So this is a multi-language problem
with both Java (netscape.javascript.JSObject) and JavaScript being
involved. I think we can handle that.

I spent a month earlier this year doing an integration for a customer in
an Oracle Forms environment that involved Java, Oracle Forms PL/SQL, and
some JavaScript. Much of last year was Java EE web apps where Java, XML,
XSLT, XHTML, CSS and SQL figured. Right now I am working ESB
integrations where Java is important but less than 50 percent.

Most of us spend quality time doing hybrid work. Sometimes a problem is
a one-language problem but often it's not. We can't get too picky about
what we'll look at and what we won't. As long as Java is involved to
some extent I think it's worth a first look.

I agree that an SSCCE is called for in any case.

Since the OP's problem stems from their Java code, the fact that what they
published was not is relevant.

At no point did I suggest that the question was inappropriate for this forum.

The OP has been around this newsgroup for far too long to be ignorant of the
smart ways to ask questions here.
 
L

Lew

Richard said:
Arved Sandstrom wrote ..
Lew said:
... SSCCE ... [context restored]
I agree that an SSCCE is called for in any case.

Thanks for the replies. I'll cut it down to just the jsobject.call(m, ARGS)
test tomorrow, but for now: -

Thanks for this fragment of your problem. The missing fragment is what went
wrong. Please copy and paste the actual output or errors and describe what you
expect instead. You haven't even told us what the error is!
import java.applet.Applet;
import netscape.javascript.JSObject;
import netscape.javascript.JSException;

public class JavaJSTest extends Applet {

JSObject laundry;
Object rinseArgs[] = new Object[1];

public synchronized void init() {

System.out.println("Starting Tests. . .");

JSObject window = JSObject.getWindow(this);

final String createLaundry =
"(function(){" +
"function Laundry(){" +
"this.launder = function(JSObject){" +
"alert('In Laundry');" +
"return JSObject;}}" +
"return new Laundry();" +
"})();";

laundry = (JSObject)window.eval(createLaundry);

// Test function calls
String str = (String) window.eval("getString();");
if (!str.equals("Hello, world!")) {
throw new RuntimeException(); // test failed
}
Number num = (Number) window.eval("getNumber()");
if (num.intValue() != 5) {
throw new RuntimeException(); // test failed
}
// Test field access
JSObject res = (JSObject) window.eval("new cities();");
if (!((String) res.getMember("b")).equals("Belgrade")) {
throw new RuntimeException(); // test failed
}
res.setMember("b", "Belfast");
if (!res.getMember("b").equals("Belfast")) {
throw new RuntimeException(); // test failed
}
// Test CALL
Boolean ans = (Boolean)res.call("d", null);

Could this possibly be where the error occurs?
System.out.println("ans is " + ans.booleanValue());

Really, 'System.out.println()'?

Check out java.util.logger or log4j.
// Test CALL with param
rinseArgs[0] = new String("A param");
Boolean pans = (Boolean)res.call("e", rinseArgs);
System.out.println("param ans is " + pans.booleanValue());

// Test array access
res = (JSObject) window.eval("getTestArray();");
if (!((String) res.getSlot(0)).equals("foo") ||
!((String) res.getSlot(1)).equals("bar")) {
throw new RuntimeException(); // test failed
}

Could this possibly be where the error occurs?
res.setSlot(1, "baz");
if (!((String) res.getSlot(1)).equals("baz")) {
throw new RuntimeException(); // test failed
}
res.setSlot(2, "qux"); // Define new array element
if (!((String) res.getSlot(2)).equals("qux")) {
throw new RuntimeException(); // test failed
}
res.removeMember("b");
try {
res.getMember("b");
// throw new RuntimeException(); // test failed

For this sort of thing, 'IllegalStateException' is a good match.
System.out.println("This browser does not support
removeMember"); // test failed
} catch (JSException e) {
// Member should not be present any more
}

System.out.println(". . .Tests complete");
}

public void hello() {
System.out.println("Hello");
}

public boolean testCall(JSObject blob) {
System.out.println("In method - testCall()");

JSObject cleanBuf;
boolean retVal = false;

try {
rinseArgs[0] = blob;
System.out.println("before launder");
try {
cleanBuf = (JSObject)laundry.call("launder", rinseArgs);
}
catch (Exception e) {
throw e;
}
System.out.println("after launder");
// System.out.println("ans is " + abc.booleanValue());

System.out.println("blob.call()");
Boolean resp = (Boolean)cleanBuf.call("e",null);

Could this possibly be where the error occurs?
System.out.println("Setting retVal");
retVal = resp.booleanValue();
} catch (JSException ex) {
Exception ex2 = (Exception)ex.getWrappedException();
if(ex2 != null) {
System.out.println(ex2.getClass().getName() + " " +
ex2.getMessage());
} else {
System.out.println(ex.getClass().getName() + " " +
ex.getMessage());
}
} catch (Exception ex) {
System.out.println(ex.getClass().getName() + " " +
ex.getMessage());
}
return retVal;
}

}


And the HTML: _

<html>
<head>
<script language="javascript">
var app;

function load() {
var objectTag = "<object ";

if (/Internet Explorer/.test(navigator.appName)) {
objectTag = objectTag +
'classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93" ';
} else {
objectTag = objectTag +
'type="application/x-java-applet" ';
}

objectTag = objectTag +
'width= "0" height= "0" id="app">' +
'<param name="codebase" value="http://127.0.0.1">' +
'<param name="code" value="JavaJSTest">' +
'<param name="java_version" value="1.6+">' +
'<param name="mayscript" value="true">' +
'<param name="scriptable" value="true">' +
'</object>';

var appletDiv = document.createElement("div");
appletDiv.innerHTML = objectTag;

try {
document.body.appendChild(appletDiv);
chanG = document.getElementById("app");
}
catch(err) {
alert("Unable to append applet: -\n" +
(err.description||err.message));
chanG = null;
};

if (chanG == null) {
throw new Error("Was unable to initialize the applet");
};

var x = new cities();
var y = x.e();
alert("X = "+y);
}

// Return a string value to Java
function getString() {
return "Hello, world!";
}

function getNumber() {
return 5;
}

// Make an object with city names and an index letter.
function cities() {
var msg = "Good Bye";
this.a = "Athens";
this.b = "Belgrade";
this.c = "Cairo";
// this.e = function(){alert(msg); return true;};
// this.e = function(){if (window.console) {console.log("Message is "
+ msg)};return true;};
// this.e = function(){throw("A Wobbly");return true;};
}

cities.prototype = {
d : function(){alert("hello"); return true;}
,e : function(){alert("good-Bye"); return true;}
,f : function(param){alert("Param = " + param); return true;}
};

function getTestArray() {
return [ "foo", "bar" ];
}

function doIt() {
var list = new cities();
var reply = chanG.testCall(list);
alert("Reply = "+reply);
}

</script>
</head>
<body onload="load();">

STUFF

<input type="Button" id="btn1" value="HitMe" onclick="doIt();"/>

</body>
</html>
 
D

Daniel Pitts

Hi.

Has anyone been able to pass the ARGS parameter to JSObject's "call" method
*and* pass arguments via the "args" parameter? An example of your
work-around perhaps?

I'm having no trouble calling methods on all sorts of complex Javascript
objects but when it comes to passing the arguments array I keep getting
nullpointerexception :-(

Firefox, IE, Chrome, and Opera are all onboard and ok.

Cheers Richard Maher
Not sure if this helps, but in the past I've had to do some hacky
work-arounds to work with JSObject.

Check out:
<http://virtualinfinity.net/wordpress/tools/2008/10/11/javascript-and-java-applets/>


Hope this helps,
Daniel.
 
R

Richard Maher

Daniel Pitts said:
Not sure if this helps, but in the past I've had to do some hacky
work-arounds to work with JSObject.

Check out:
<http://virtualinfinity.net/wordpress/tools/2008/10/11/javascript-and-java-applets/>

Hi Daniel,

Thanks as always for your replies.
Hope this helps,

It certainly helped a couple of years ago (with FireFox 2.n or 3.0?) when
you first showed me your cunning solution. That was my first (well probably
about 5th as is happens) port of call.

You may not recall, but that's when I first introduced the JS
"Tier3Client.launder" function that just took a JSObject a a parameter and
returned the same JSObject which was automagically fixed/rinsed. This worked
well back in the day but now FF, IE, Chrome, and Opera (and JSObject) all
seemed to have moved on and the "fix" was looking redundant - until Safari
and its insistence on the "First Generation plug-in" :-(

The problem is my solution is not working with Safari and I think Safari has
other issues. I used to getMember("Tier3Client") on the applet window and
then call my "launder" on that. If you look at the code I posted just before
you'll see that I was trying to be "clever" and use an anonymous JS function
to return a launder function. As this could well have been an issue, I
reverted to the tried and tested method but still no joy.

Anyway, I'll give your code/solution a go shortly but I'm not hopeful given
that I can't even get a simple appletWindow.call("topLevelFunction", args)
to do other than return "null". Without arguments is not a problem.

So in the meantime if anyone knows of an example JSObject.call("sayHello",
WITHargs) that works in Safari can they please provide a pointer?

Cheers Richard Maher

PS. NO *NOT bloody EVAL* - call, Call, CALL()!
 
R

Richard Maher

Richard Maher said:
Anyway, I'll give your code/solution a go shortly but I'm not hopeful
given that I can't even get a simple appletWindow.call("topLevelFunction",
args) to do other than return "null". Without arguments is not a problem.

So in the meantime if anyone knows of an example JSObject.call("sayHello",
WITHargs) that works in Safari can they please provide a pointer?

As expected, still no joy and a nullpointer. (And now IE complains that you
can't cast a String to JSObject)

Thanks anyway.

Anyone else done this on Safari?
 
A

Arved Sandstrom

As expected, still no joy and a nullpointer. (And now IE complains that you
can't cast a String to JSObject)

Thanks anyway.

Anyone else done this on Safari?

I don't usually deal with Java applets of any kind, but this was
interesting. I worked up a Swing JApplet and have a JavaScript function
an a JSP page.

Since you mentioned Safari I did Safari 5.1.2 on Mac OS X 10.6.8 with
Java Plug-in 1.6.0_31.

The applet has text fields to take 2 numbers, a result text field, and a
"submit" button. The JavaScript function is

function addNums(one,two) {
return one+two;
}

and the important 2 lines of code in the applet are

JSObject win = JSObject.getWindow(this);
Object sum = win.call("addNums", new Object[] {num1, num2});

where 'num1' and 'num2' are java.lang.Doubles. So is 'sum'.

There is not anything more to it. It worked just fine.

AHS
 
R

Richard Maher

Hi Arved,

On 12-04-22 04:07 AM, Richard Maher wrote:
Since you mentioned Safari I did Safari 5.1.2 on

Well there goes 3 days of my life I'll never get back :-( I guess some
would say I deserve it for not being a OS/X user. I should have
pointed out that I was running Safari of Windows XP but on 2nd
thoughts, who cares? I can't see many users choosing to browse with
Safari on Windows so, in the grand scheme of things it can stay broke.
(Shame to not be able to test there though).

.. A couple of other observations on Safari Liveconnect support for
those following at home
1) removeMember is not support on WIN or OS/X (Either does Chrome for
that matter)
2) WIN Safari supports get/set Member but OS/X does not
Java Plug-in 1.6.0_31.

The applet has text fields to take 2 numbers, a result text field, and a
"submit" button. The JavaScript function is

function addNums(one,two) {
  return one+two;

}

and the important 2 lines of code in the applet are

JSObject win = JSObject.getWindow(this);
Object sum = win.call("addNums", new Object[] {num1, num2});

where 'num1' and 'num2' are java.lang.Doubles. So is 'sum'.

There is not anything more to it. It worked just fine.

Yep, pretty wonderful and useful stuff eh?

Thanks for testing it for me.

Cheers Richard Maher
 
A

Arved Sandstrom

Hi Arved,

On 12-04-22 04:07 AM, Richard Maher wrote:
Since you mentioned Safari I did Safari 5.1.2 on

Well there goes 3 days of my life I'll never get back :-( I guess some
would say I deserve it for not being a OS/X user. I should have
pointed out that I was running Safari of Windows XP but on 2nd
thoughts, who cares? I can't see many users choosing to browse with
Safari on Windows so, in the grand scheme of things it can stay broke.
(Shame to not be able to test there though). [ SNIP ]

Thanks for testing it for me.

Cheers Richard Maher

I'm not one to resist a challenge, I tested the applet against Safari on
my Windows XP, and it worked also.

Safari 5.0.3, Windows XP, JDK 1.6.0_31 (and corresponding plugin).

FWIW my test environment is very spare. The JApplet itself is
uncomplicated, and the 2 lines I showed you are the only ones that talk
to JavaScript. The JavaScript is the function I showed, and it's the
only JavaScript in the page that contains the applet. And my applet tag
*is* an <applet> tag, not an <object> tag, with only the 'code' and
'archive' attributes. I'm not saying you want to, or can, simplify that
much (considering you want to support many browsers) but it's what
worked for me in Safari on both Mac OS X and Win XP for this scenario.

AHS
 

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