ID: 9162
User Update by: [EMAIL PROTECTED]
Status: Open
Bug Type: Class/Object related
Description: Java support corrupts Hashtables

Just in case you were confused, the java method getSomething() should return (String) 
myhash.get( "myname" ), and the PHP call should be my_java->getSomething( $my_hash ). 
You get the idea.

Previous Comments:

[2001-02-07 15:28:44] [EMAIL PROTECTED]
This bug is with the Java support in PHP4. PHP seems to try to treat Java Hashtable 
objects as PHP-native arrays, with several negative impacts. First of all, Java 
Hashtables have no internal concept of ordering or null termination, nor do they have 
an internal "current" pointer. Therefore, if you try to travserse a Java Hashtable as 
you would a PHP array, you will run off the end! However, since the Hashtable is not 
an object (under PHP), you cannot call $my_hash->get( "x" ) or $my_hash->put( "y" ).

Second of all, if you try to pass such a Hashtable BACK to a Java class method, you 
will find that the Hashtable has been corrupted, and all your datatypes changed and 
you will get various NullPointerExceptions or illegal cast exceptions.

It seems to me the most natural approach at this point would be to just treat Java 
Hashtables as generic objects, and therefore retain the get() and put() methods. That 
way you don't corrupt the Hashtable, and you don't let anyone go off the end of any 

I don't know if this kind of thing happens with other Java object classes.

There is a workaround whereby one can, in Java, explicitly repair a corrupted 
Hashtable, but that is pretty ugly. If you are interested in looking at the 
workaround, email me.

Here is a code snippet illustrating what I mean:

public class MyClass {

    public MyClass() { }

    public Hashtable makeHash( int ikey, int ival, String skey, String sval ) {
        Hashtable myhash = new Hashtable();
        myhash.put( ikey, ival );
        myhash.put( skey, sval );
        myhash.put( "myname", "joe" );
        return myhash;

    public String getSomething( Hashtable myhash ) {
        return myhash.get( "myname" );



$my_java = new Java( "MyClass" );
$my_hash = my_java->makeHash( 1,2,"yourname", "steve" );

// watch this:

print( implode( ",", $my_hash ) );   // explosion! off the end of the array

// or, 

print( $my_java->getSomething() );  // java exception!



Full Bug description available at:

PHP Development Mailing List <>
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
To contact the list administrators, e-mail: [EMAIL PROTECTED]

Reply via email to