Java History – Influence of Pascal and Delphi on Java

historyjavapascal

I was reading in the side bar of the Java language wiki page and it says it was influenced by Pascal and Delphi.
_{this isn't the fact anymore, there are no references to Delphi on the entire referenced wiki page as of this edit, probably should remove all references to Delph from this question as well}

At first glance Java appears to just be C++ with a garbage collector, and no pointers. Delphi and Java both came out the same year.

I am curious if someone who knows Java and Pascal / Delphi really well could look at Java and say "Feature X in Java is influenced by feature Y in Pascal (or Delphi)."

Additionally was the influence in later versions of Java (so the feature from Pascal or Delphi didn't show up until Java version Z), or was it actually in the seeds of the Java language? Delphi and Java both came out the same year, so Delphi's influence in the genesis of Java seems less likely.

Alternatively it may be that Delphi or Pascal influenced the Java Platform in some other way, and not the language specifically.

[This was rewritten to be clearer. That may have changed the scope of the question to the point the existing comments and answers don't fit. My intention was to clarify and not change.]

Best Answer

One definitive influence on java was the idea and use of p-Code (pseudo-code) in the Pascal package from UCSD. It was popular in the early days of the Apple-II computer.

This idea of p-Code is very similar to that of Java.

Related Solutions

Java History – Core API Packages of Java 1.0

Per Wikipedia, the first formally released version of Java was 1.0.2, on Jan 23 1996.

The first stable version was the JDK 1.0.2. is called Java 1

There's an archive of Java 1.0.2 and all related documentation here:

JDK 1.0.2 API reference (book format)

JDK 1.0.2 API reference (javadoc format)

Java tutorial

Java language specification (link broken, wayback'd here)

Java virtual machine specification

There appears to be a download of the JDK 1.0.2 bits here

http://www.pascal-man.com/download/download-jdk.shtml

It works for me at the time of writing.

Java 1.0.2 on Windows 7 x64

BEHOLD THE RAW UNMITIGATED POWER OF JAVA 1.0.2

In the language spec, the following classes are referred to (single citation, not exhaustive citations):

Class (section 4.3.1)
String (section 4.3.1)
Object (section 4.3.2)
Random (section 4.4)
Thread (section 17.2)
ThreadGroup (section 17.2)
Throwable (section 11)
Error (section 11.2)
loads and loads of errors, all under java.lang (section 11.5.2.1 - 11.5.2.2)
RuntimeException (section 11.2.1)
the "Array classes", [I, and so on (section 10.8)

... at which point I stopped looking because, technically, [I, et. al. aren't in the java.lang, java.util, or java.io packages.

Example:

class Test {
  // Compare namespaces of built-ins object and int[]
  public static void main(String[] args){
    int[] arr = new int[0];
    Object obj = new Object();

    Class arrClass = arr.getClass();
    Class objClass = obj.getClass();

    Class arrSuper = arrClass.getSuperclass();

    System.out.println("plain jane Object - " + objClass.getName());
    System.out.println();
    System.out.println("int[] - "+arrClass.getName());
    System.out.println("super of int[] - "+arrSuper.getName());
  }
}

Outputs

enter image description here

Behavior is consistent between modern and 1.0.2

enter image description here

Delphi Pascal – Best Practices for Implementing MVVM and MVC

You should look into Spring4D as it already contains nullable types (similar implementation as yours with a little extra operator overloading) and way more powerful collection types than those in the RTL. They are also interfaced based which is very handy because you don't have to worry about lifetime management especially when passing them around.

For cross referencing problems I am suggesting coding against interfaces and use these as reference in another implementation rather than 2 implementations knowing each other.

As for the MVVM part you might look into DSharp which has a first version of a Caliburn Micro port for Delphi. It is very early stage and hardly documented but you might get some ideas how to achieve MVVM in Delphi using loosely coupled GUI and business logic connected with data bindings. The Blaise Pascal magazine had two articles about it if you are more interested.

P.S. I guess you mean you are using XE6 as that is the latest version.

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