What is PHP4 ext/java? PHP4 ext/java provides a simple and effective means for creating and invoking methods on Java objects from PHP. The JVM is created using JNI, and everthing runs in-process. Two examples are provided, jver and jawt, to illustrate usage of this extension. A few things to note: 1) new Java() will create an instance of a class if a suitable constructor is available. If no parameters are passed and the default constructor is private, then an instance of the class is returned instead. This is useful as it provides access to classes like "java.lang.system" which expose most of their functionallity through static methods. 2) Accessing a member of an instance will first look for bean properties then public fields. In other words, "print $date.time" will first attempt to be resolved as "$date.getTime()", then as "$date.time"; 3) Both static and instance members can be accessed on an object with the same syntax. Furthermore, if the java object is of type "java.lang.Class", then static members 4) Exceptions raised result in PHP warnings, and null results. 5) Overload resolution is in general a hard problem given the differences in types between the two languages. This being said, the current support is pretty lame and I intend to improve it. The current algorithm is to pick the first method with the right name (ignoring case!) and number of parameters - I warned you it was lame! Build and execution instructions: Given the number of platforms and providers of JVMs, no single set of instructions will be able to cover all cases. So in place of hard and fast instructions, below are a working examples for a number of free and commercial implementations and platforms. Please adjust the paths to suit your installation. Also, if you happen to get this to work on another JVM/platform combination, please let me know, particularly if a unique build or execution setup was required. This function has been tested in both CGI and Apache (apxs) modes. As the current design requires shared libraries, this support can not be linked statically into Apache. Finally, it is worth noting that no JVMs are created until the first Java call is made. This not only eliminates unnecessary overhead if the extension is never used, it also provides error messages directly back to the user instead of being burried in a log some place. Additionally, on Unix, the loading of the shared library which implements the JVM is also deferred until first use. ======================================================================== === JVM=Kaffe 1.0.4 (as delivered with OS), OS=Redhat Linux 6.1 === ======================================================================== build instructions: ./configure --with-java php.ini: [java] java.library=/usr/lib/kaffe/libkaffevm.so java.library.path=/usr/lib/kaffe:/home/rubys/php4/modules java.class.path=/usr/share/kaffe/Klasses.jar:/home/rubys/php4/modules/php_java.jar extension_dir=/home/rubys/php4/modules extension=libphp_java.so ======================================================================== === JVM=Kaffe 1.0.5 (built from source), OS=Redhat Linux 6.1 === ======================================================================== build instructions: ./configure --with-java php.ini: [java] java.library=/usr/local/lib/libkaffevm.so java.library.path=/usr/local/lib/kaffe:/home/rubys/php4/modules java.class.path=/usr/local/share/kaffe/Klasses.jar:/home/rubys/php4/modules/php_java.jar extension_dir=/home/rubys/php4/modules extension=libphp_java.so ======================================================================== === JVM=IBM 1.1.8, OS=Redhat Linux 6.1 === ======================================================================== build instructions: ./configure --with-java=/home/jdk118 php.ini: [java] java.library=/home/jdk118/lib/linux/native_threads/libjava.so java.class.path=/home/jdk118/lib/classes.zip:/home/rubys/php4/modules/php_java.jar extension_dir=/home/rubys/php4/modules extension=libphp_java.so ======================================================================== === JVM=Sun/Blackdown 1.2pre-release-v2, OS=Linux (glibc 2.1) === ======================================================================== build instructions: ./configure --with-java=/usr/local/lib/jdk1.2 php.ini: [java] java.library=/usr/local/lib/jdk1.2/jre/lib/i386/libjava.so java.library.path=/usr/local/lib/jdk1.2/jre/lib/i386/classic:/usr/local/lib/jdk1.2/jre/lib/i386/native_threads:/usr/local/lib/jdk1.2/jre/lib/i386:/var/tmp/work/php4/modules java.class.path=/usr/local/lib/jdk1.2/jre/lib/rt.jar:/usr/local/lib/jdk1.2/jre/lib/i18n.jar:/var/tmp/work/php4/modules/php_java.jar extension_dir=/var/tmp/work/php4/modules extension=libphp_java.so You may also have to adapt your LD_LIBRARY_PATH environment variable, if you didn't add the jdk library paths to /etc/ld.so.conf : LD_LIBRARY_PATH="/usr/local/lib/jdk1.2/jre/lib/i386:/usr/local/lib/jdk1.2/jre/lib/i386/classic:/usr/local/lib/jdk1.2/jre/lib/i386/native_threads:$LD_LIBRARY_PATH" ======================================================================== === JVM=Sun JDK 1.1.8, OS=Windows NT 4 === ======================================================================== build instructions: SET JAVA_HOME=D:\jdk1.1.8 msdev ext\java\java.dsp /MAKE "java - Win32 Debug_TS" php.ini: [java] java.class.path="D:\jdk1.1.8\lib\classes.zip;F:\PHP4\Debug_TS\php_java.jar" extension=php_java.dll ======================================================================== === JVM=Sun JDK 1.2.2, OS=Windows NT 4 === ======================================================================== build instructions: SET JAVA_HOME=D:\jdk1.2.2 msdev ext\java\java.dsp /MAKE "java - Win32 Debug_TS" php.ini: [java] java.class.path=F:\PHP4\Debug_TS\php_java.jar extension=php_java.dll