For Java Language specifications see
JLS
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Glossary TOC
The gloss of the Web was lost on the fly
who intended to miss it as he passed by
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abstract An abstract class or method.
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boolean The boolean type ( a logic valued data type)
- bit and byte A bit is a single binary
value in a list of binary values ( i.e 1001 includes four bits)
while a byte is a set of eight bits or 256 pieces of information
(i.e. 1001 1101 is a byte).
- byte integer data type (1 byte) -128 to 127.
- browser refers to a
computer program which allows the user to
access the information over the internet in a
simple and easy way. By browser we will typically mean an
http type browser which allows for the transfer of
graphics and convenient viewing of text.
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- case switch/case - control structure with
ability to choose different paths e.g. assume that choice is an integer 1,2 ,3,...
switch(choice)
    { case 1: ...
      break;
      case 2: ...
      break;
...
      default:...
      break;
    }
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cast is a process in which one data type is recast to another
relatively compatible data type. E.g.
double realnum=0.5;
int i;
...
i = (int) realnum;
"realnum" is recast as an integer so that the value of "i" may be set.
- catch Error detection and correction
structure which allows the programmer to catch an exception which
could otherwise dump the program. E.g.
        public Object clone(){ //begin clone
          try{ //begin try
          return super.clone();
              } //end try
      catch(CloneNotSupportedException e){ // begin catch
          return null; //if there is a catch
          } //end catch
          } //end cloning structure for point
- char The unicode character type
- allows the programmer to use a single character but not as a
string .
- class Defines a class type. A class is
the terminonolgy generally used for a programming object. This is also used as a suffix on machine coded objects , methods and executable programs
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- do part of the do/while loop control structure e.g.
a= 1;
b = 0;
do
  { a = a+ 1;
    b = b+2;
  }
while (a < 10) ; // for a =9 or less continue
- double double precision floating point data type.
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- else Used as a control structure in an if statement - see also if.
- extends Used by a progeny class to indicate the parent class.
The progeny then inherits the properties and qualities of the parent class.
- float Single precision floating point.
- for Beginning of a for loop e.g.
for(i=0;i<11;i++)
          { //begin for loop exectution
          num = num + i;
          count = count + 1;
          } //end for loop execution
or
for(i=0;(sky="thelimit")&&(moon="bright");i<11;i++)
          { //begin for loop exectution
          num = num + i;
          count = count + 1;
          } //end for loop execution
note that the for statement can contain many conditions. Observe that the execution
statements are framed inside a pair of curly braces{}.
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- gif
- Graphics Interchange Format - A rigid graphical file
description system.
- Graphical User
Interface refers specifically to point and click view
screen technology.
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HTML - HyperText Markup Language- The
computer language used to format an webpage. This
language is a subset of the language CGML.
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- if The beginning of a decision structure e.g.
if(i==j){
num=7;
moon="high";
          } // end if
else if (i==j+1){
num=6;
moon="low";
          } //end else if
else {
num=8;
moon="middle";
          } //end else
- implements is used in class definitions to invoke other
class methods or interfaces within the definition.
public class point implements Cloneable{
          public int x;
          public int y;
        public Object clone(){ //begin clone
          try{ //begin try
          return super.clone();
              } //end try
      catch(CloneNotSupportedException e){ // begin catch
          return null; //if there is a catch
          } //end catch
          } //end cloning structure for point
          } //end point def
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import calls the given library package to be loaded
when needed by the compiler. (e.g.
import java.applet.*
will make the java applet library available during the
compilation of the program.)
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inheritance A feature of object oreiented programming
languages. Specifically, it allows extending classes or progeny to
use all of the public procedures and variables of the parent class.
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int is the primitive integer data type. The minimum
value is -2147483648 and the maximum value is 2147483647. (e.g.
- jpeg - Joint
Photographic Expert Group - a rigid graphical file
description system and file compression scheme
which can use millions of colors.
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- long - integer data type with range of approximately -1019 to 1019.
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- method - inclusive term for java defined functions, subroutines etc.. A method is essentially a java object.
- NaN - Not a Number .
- mpeg
- Moving Pictures Expert Group- A set of ordered graphical
files which can produce a moving picture.
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new - is used to create an instance of a programmer defined object type or to initialize a new variable.
public Employee(String n, double s)
    { name=n;
      salary=s;
    }
    Number007= new Employee("Bond, James Bond", 1000007);
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null - used to return a null value in a function method.
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object Generic name for classes. In particular
in Java an object is a specific instance of a class.
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private - essentially defines an object as local or pertaining to the class.
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protected - objects available to subclasses etc.
- public - objects available to the world.
- Portable A portable program or file
system is one that can be used on several different computers
without using a converter. The standard system for portable text
files is ASCII. Java is an example of a portable programming
language.
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return - the result of a method especially a function method. The return in a method gives the value or values to be returned by the function to the main or subroutine that calls the function. A return is not needed if the method is void.
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- short - integer data type (2 bytes) approximately -32,000 to 32,000.
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static - static fields do not change from one instance of a class to another. Static methods belong to a class and do not operate on any particular instance of the class.
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subclass - a child of a class
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super
public Object clone(){ //begin clone
  try{ //begin try
  return super.clone();
      } //end try
catch(CloneNotSupportedException e){ // begin catch
  return null; //if there is a catch
  } //end catch
  } //end cloning structure for point
  } //end point def
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superclass - the super calss object or constructor, see for instance super.
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switch
switch(count){ \\begin case checks
      case 2: note="high"; break;
      case 5: note="low"; break;
      case 17: note="out_of_range";break;
      default: note="clear";break;
             } //end case checks
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this - refers to the object on which the method operates.
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throw - used to detect and handle possible exceptions or error in the program. Suppose you wish to check a string for the correct length. You count the characters as "n", e.g.
{ while (...)
    if (ch==-1) //EOF encountered
     { if (n < correctLength)
        throw new EOFException();
     } //end if
    } //endif
} //endwhile
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true - boolean type.
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try .
// Read a parameter interpret as hexidecimal and //convert to color.
protected Color getColorParameter(String name){
String value=this.getParameter(name);
int intvalue;
try{ intvalue=Integer.parseInt(value,16);} // end try
catch(NumberFormatException e){return null;} // end catch
return new Color(intvalue);
} // end get Color
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- UNIX The UNIX operating system
originally grew out of the the MULTICS operating system developed
for a General Electric computer system. This was the product of a
consortium of computer related industries. When the consortium
failed to produce a satisfactory product, a computer operating
system was developed on a PDP-7
at Bell Labs by Ken Thompson,
one of the participants in the original MULTICS project.
Ironically, it was dubbed UNIX because it actually could handle
multitasking effectively. UNIX created the open system environments
along with security measures that made the internet possible. Many
of the file transfer protocols grew out of the UNIX concept.
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void used for methods that are not really functions. No return value is needed.
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while loop control structure- see also do/while .
For Java Language specifications see
JLS
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