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Arrays
C# COBOL VB.NET Java
int[] nums = {1, 2, 3}; for (int i = 0; i < nums.Length; i++) { Console.WriteLine(nums[i]); }
// 5 is the size of the array string[] names = new string[5]; names[0] = "David"; names[5] = "Bobby"; // Throws System.IndexOutOfRangeException // C# can't dynamically resize an array. Just copy into new array. string[] names2 = new string[7]; Array.Copy(names, names2, names.Length); // or names.CopyTo(names2, 0);
float[,] twoD = new float[rows, cols]; twoD[2,0] = 4.5f;
int[][] jagged = new int[][] { new int[] {1, 2}, new int[] {3, 4, 5}, new int[] {6, 7, 8, 9} }; jagged[0][4] = 5;
declare nums = table of binary-long (1 2 3)
declare names as string occurs 5 *> Can also do: declare names-again as string occurs any set size of names to 5
set names(1) to "David" *> first element indexed as 1 *> ...but can also use zero based subscripting: set names[0] to "David" *> first element indexed as 0
*>set names(6) to "Bobby" *> throws System.IndexOutOfRangeException
*> COBOL does not have direct resizing syntax but achieves similar *> results using 'reference modification' syntax: declare names2 as string occurs 7 set names2[0:size of names] to names *> Resizing to a smaller size is even simpler: set names2 to names[0:3]
declare twoD as float-short occurs any, any. declare rows as binary-long = 3 declare cols as binary-long = 10 set size of twoD to rows, cols
declare jagged = table of (table of binary-long(1 2) table of binary-long(3 4 5) table of binary-long(6 7 8 9))
*> Can also do: declare jagged2 as binary-long occurs any, occurs any set size of jagged2 to 3 set size of jagged2(1) to 5 set jagged2(1 5) to 5
Dim nums() As Integer = {1, 2, 3} For i As Integer = 0 To nums.Length - 1 Console.WriteLine(nums(i)) Next
' 4 is the index of the last element, so it holds 5 elements Dim names(4) As String names(0) = "David" names(5) = "Bobby" ' Throws System.IndexOutOfRangeException
' Resize the array, keeping the existing values (Preserve is optional) ' Note, however, that this produces a new copy of the array -- ' it is not an in-place resize! ReDim Preserve names(6)
Dim twoD(rows-1, cols-1) As Single twoD(2, 0) = 4.
Dim jagged()() As Integer = { New Integer(2) {1, 2}, New Integer(3) {3, 4, 5}, New Integer(4) {6, 7, 8, 9}} jagged(0)(4) = 5
public class Arrays { public static void main(String args[]) { int nums[] = { 1, 2, 3 };
String names[] = new String[5];
names[0] = "David";
// names[5] = "Bobby"; // throws ArrayIndexOutOfBoundsException
// Can't resize arrays in Java
String names2[];
// Copy elements from an array names2 = java.util.Arrays.copyOfRange(names, 0, 3);
float twoD[][];
int rows = 3; int cols = 10;
twoD = new float[rows][cols];
int[][] jagged = { { 1, 2 }, { 3, 4, 5 }, { 6, 7, 8, 9 } };
int[][] jagged2 = new int[3][]; jagged[0] = new int[5]; jagged[0][4] = 5;
}
}
Choices
C# COBOL VB.NET Java
greeting = age < 20? "What's up?" : "Hello";
// Good practice is that all consequents are enclosed in {} // or are on the same line as if. if (age < 20) greeting = "What's up?"; else { greeting = "Hello"; }
// Multiple statements must be enclosed in {} if (x != 100 && y < 5) { x *= 5; y *= 2; }
//No need for _ or : since ; is used to terminate each statement.
if (x > 5) { x *= y; } else if (x == 5) { x += y; } else if (x < 10) { x -= y; } else { x /= y; }
// Every case must end with break or goto case switch (color) // Must be integer or string { case "pink": case "red": r++; break; case "blue": b++; break; case "green": g++; break; default: other++; break; // break necessary on default }
declare age as binary-long = 10 declare greeting as string *>greeting = age < 20? has no directly equivalent syntax in COBOL
if age < 20 move "What's up?" to greeting else move "Hello" to greeting end-if
declare x as binary-long = 200 declare y as binary-long = 3 if x not = 100 and y < 5 multiply 5 by x multiply 2 by y end-if
*> evaluate is preferred in COBOL rather than if/else if/else evaluate x when > 5 multiply y by x when 5 add y to x when < 10 subtract y from x when other divide y into x end-evaluate
declare color as string = "blue" declare r b g other-color as binary-long evaluate color *> can be any type when "pink" when "red" add 1 to r when "blue" add 1 to b when "green" add 1 to g when other add 1 to other-color end-evaluate
greeting = IIf(age < 20, "What's up?", "Hello")
' One line doesn't require "End If" If age < 20 Then greeting = "What's up?" If age < 20 Then greeting = "What's up?" Else greeting = "Hello"
' Use : to put two commands on same line If x <> 100 And y < 5 Then x *= 5 : y *= 2
' Preferred If x <> 100 And y < 5 Then x *= 5 y *= 2 End If
' To break up any long single line use _ If whenYouHaveAReally < longLine And _ itNeedsToBeBrokenInto2 > Lines Then _ UseTheUnderscore(charToBreakItUp)
If x > 5 Then x *= y ElseIf x = 5 Then x += y ElseIf x < 10 Then x -= y Else x /= y End If
Select Case color ' Must be a primitive data type Case "pink", "red" r += 1 Case "blue" b += 1 Case "green" g += 1 Case Else other += 1 End Select
public class choices {
public static void main(String[] args) { int age = 10; String greeting = age < 20? "What's up?" : "Hello";
if (age < 20) { greeting = "What's up?"; } else { greeting = "Hello"; }
int x = 200; int y = 3;
if (x != 100 && y < 5) { x = 5 * x; y = 2 * y; }
if (x > 5) { x = x * y; } else if (x == 5) { x = x + y; } else if (x < 10) { x = x - y; } else { x = x / y; }
String color = "blue"; int r = 0, b = 0, g = 0, other_color = 0;
if (color.equals("pink") || color.equals("red")) { r++; } else if (color.equals("blue")) { b++; } else if (color.equals("green")) { other_color++; }
}
}
Classes Interfaces
C# COBOL VB.NET Java
//Accessibility keywords public private internal protected protected internal static
// Inheritance class FootballGame : Competition { ... }
// Interface definition interface IAlarmClock { ... }
// Extending an interface interface IAlarmClock : IClock { ... }
// Interface implementation class WristWatch : IAlarmClock, ITimer { ... }
*> Accessibility keywords *>public *>private *>internal *>protected *>protected internal *>static
class-id Competition.
end class.
*> Inheritance class-id FootballGame inherits type Competition.
end class.
*> Interface definition interface-id IClock.
end interface.
interface-id ITimer.
end interface.
*> Extending an interface interface-id IAlarmClock inherits type IClock.
end interface.
*> Interface implementation class-id WristWatch implements type IAlarmClock, type ITimer.
end class.
' Accessibility keywords Public Private Friend Protected Protected Friend Shared
' Inheritance Class FootballGame Inherits Competition ... End Class
' Interface definition Interface IAlarmClock ... End Interface
' Extending an interface Interface IAlarmClock Inherits IClock ... End Interface
' Interface implementation Class WristWatch Implements IAlarmClock, ITimer ... End Class
//Accessibility keywords public private // The closest counterpart to .NET's "internal" is specified // by ommitting the visibility keyword, though this "default" // visibility has some behaviour differences. protected static
// Inheritance class FootballGame extends Competition { ... }
// Interface definition interface IAlarmClock { ... }
// Extending an interface interface IAlarmClock extends IClock { ... }
// Interface implementation class WristWatch implements IAlarmClock, ITimer { ... }
Comments
C# COBOL VB.NET Java
// Single line /* Multiple line / /// XML comments on single line /* XML comments on multiple lines */
$set sourceformat(variable)
- Single line "old-style" COBOL comment with '*' in column 7 *> inline comment may follow COBOL statements etc. *>> XML comments
' Single line only REM Single line only ''' XML comments
// Comments on a single line
/* C style multi-line comments */
Constants
C# COBOL VB.NET Java
const int MAX_STUDENTS = 25;
// Can set to a const or var; may be initialized in a constructor readonly float MIN_DIAMETER = 4.93f;
class-id Students.
*> optionally public etc., and may reference constants in other classes 01 MAX_STUDENTS binary-long constant value 25 + 3.
*> Can set to a const or var; may be initialized in a constructor 01 MIN_DIAMETER float-short value 4.93 initialize only.
method-id Main(). display MAX_STUDENTS display MIN_DIAMETER end method.
end class.
Const MAX_STUDENTS As Integer = 25
' Can set to a const or var; may be initialized in a constructor ReadOnly MIN_DIAMETER As Single = 4.
public class constants { // constant value cannot be changed ; public static final int MAX_STUDENTS = 25 + 3;
// This value can be assigned at declaration // OR // assigned in constructor // (not both) public final float MIN_DIAMETER = 4.93f;
}
Constructors Destructors
C# COBOL VB.NET Java
class SuperHero { private int _powerLevel;
public SuperHero() { _powerLevel = 0; }
public SuperHero(int powerLevel) { this._powerLevel= powerLevel; }
˜SuperHero() { // Destructor code to free unmanaged resources. // Implicitly creates a Finalize method } }
class-id Heater. 01 _powerLevel binary-long.
method-id new. set _powerLevel to 0 end method.
method-id new (powerLevel as binary-long). set _powerLevel to powerLevel end method.
$if JVMGEN set method-id Finalize override protected. *> JVM finalizer method. end method. $else method-id Finalize override protected. *> .NET finalizer method. end method. $end end class.
Class SuperHero Private _powerLevel As Integer
Public Sub New() _powerLevel = 0 End Sub
Public Sub New(ByVal powerLevel As Integer) Me._powerLevel = powerLevel End Sub
Protected Overrides Sub Finalize() ' Desctructor code to free unmanaged resources MyBase.Finalize() End Sub End Class
public class ConstructorsDestructors { private int _powerOevel;
public ConstructorsDestructors(int powerLevel) { _powerOevel = powerLevel; }
@Override public void finalize() { // finalizer code }
}
Data Types
C# COBOL VB.NET Java
Value Types bool byte, sbyte char short, ushort, int, uint, long, ulong float, double decimal DateTime (a framework type)
Reference Types object string
Initializing bool correct = true; // Can also infer variable type if the value has a well-defined type var incorrect = false; // automatically a bool byte b = 0x2A; // hex // no support for octal literals // no support for binary literals object person = null; string name = "Dwight"; char grade = 'B'; DateTime now = DateTime.Now; // No support for date/time literals decimal amount = 35.99m; float gpa = 2.9f; double pi = 3.14159265; long lTotal = 123456L; short sTotal = 123; ushort usTotal = 123; uint uiTotal = 123; ulong ulTotal = 123;
Type Information int x; Console.WriteLine(x.GetType()); // Prints System.Int Console.WriteLine(typeof(int)); // Prints System.Int Console.WriteLine(x.GetType().Name); // prints Int Type Conversion float d = 3.5f; int i = (int)d; // set to 3 (truncates decimal)
*>Value Types *>condition-value *>binary-char (unsigned) *>character *>binary-short, binary-long, binary-double (unsigned) *>float-short, float-long *>decimal *>DateTime (a framework type)
*>Reference types *>object *>string
*>Initializing declare correct as condition-value = true *> Can also infer variable type if the value has a well-defined type declare incorrect = false *> automatically a condition-value declare b as byte = h"2a" *> hex declare o as byte = o"52" *> octal declare b2 as byte = b"101010" *> binary declare person as object = null declare nam as string = "Dwight" declare grade as character = "B" declare now as type DateTime = type DateTime::Now *> No support for date/time literals declare amount as decimal = 35. declare gpa as float-short = 2. declare pi as float-long = 3. declare lTotal as binary-double = 123456 declare sTotal as binary-short = 123 declare usTotal as binary-short unsigned = 123 declare uiTotal as binary-long = 123 declare ulTotal as binary-long unsigned = 123
*>Type Information declare x as binary-long display x::GetType *> Prints System.Int display type of binary-long *> Prints System.Int display x::GetType::Name *> Prints Int *>Type Conversion declare f as float-short = 3.5 *> automatic conversion declare i = f as binary-long *> set to 3 (truncates decimal)
end program.
program-id Legacy. *> COBOL types not supported directly by other languages. *> Visual COBOL supports these types on all platforms. *> Only a few examples here 01 displayNumber pic 9(9).99. 01 computeNumber pic 9(9)V99. 01 alphaNumberic pic a(23). 01 binaryStorage pic x(12). *> Also groups and redefines - a few examples 01 arecord. 03 aSubRecord pic x(10). 03 aUnion pic 9(10) redefines aSubrecord. end program.
Value Types Boolean Byte, SByte Char Short, UShort, Integer, UInteger, Long, ULong Single, Double Decimal Date
Reference Types Object String
Initializing Dim correct As Boolean = True ' No mechanism for automatic typing Dim b As Byte = &H2A 'hex Dim o As Byte = &O52 'octal ' No support for binary literals Dim person As Object = Nothing Dim name As String = "Dwight" Dim grade As Char = "B"c Dim now As Date = Datetime.Now Dim past As Date = #12/31/2007 12:15:00 PM# Dim amount As Decimal = 35.99@ Dim gpa As Single = 2.9! Dim pi As Double = 3. Dim lTotal As Long = 123456L Dim sTotal As Short = 123S Dim usTotal As UShort = 123US Dim uiTotal As UInteger = 123UI Dim ulTotal As ULong = 123UL
Type Information Dim x As Integer Console.WriteLine(x.GetType()) ' Prints System.Int Console.WriteLine(GetType(Integer)) ' Prints System.Int Console.WriteLine(TypeName(x)) ' Prints Integer Type Conversion Dim d As Single = 3. Dim i As Integer = CType(d, Integer) ' set to 4 (Banker's rounding) i = CInt(d) ' same result as CType i = Int(d) ' set to 3 (Int function truncates the decimal)
import java.math.BigDecimal; import java.time.LocalDateTime;
public class DataTypes { // Java doesn't have value types, though it does have // "primitives" avaialble for the common types, which // are similar in some respects // boolean // byte // char // short, int, long // float, double // BigDecimal (a framework type)
@SuppressWarnings("unused") public static void main(String[] args) { boolean correct = true; // no mechanism for automatic typing byte b = 0x2a; // hex byte o = 052; // octal byte b2 = 0b101010; // binary (Java 7 onwards) Object person = null; String nam = "Dwight"; char grade = 'B'; LocalDateTime now = LocalDateTime.now(); // No support for date/time literals BigDecimal amount = new BigDecimal(35.99); float gpa = 2.9f; double pi = 3.14159265; long lTotal = 123456; short sTotal = 123;
// Java has no unsigned integer types
// Java reflection does not work on primitive types. Integer x = new Integer(0); System.out.println(x.getClass().getCanonicalName());
// Type conversion short f = (short) 3.5 ; // must use cast to convert int i = f; // set to 3 (truncation) }
}
Delegates Events
C# COBOL VB.NET Java
delegate void MessageHandler(string message);
class DelegatesEvents { static event MessageHandler MessageArrived;
static void Main() { // explicit delegate construction new MessageHandler(MyHandler);
// implicit delegate construction MessageHandler handler = MyHandler;
// subscribe to an event MessageArrived += MyHandler;
// raise the event MessageArrived("Test message");
// unsubscribe from the event MessageArrived -= MyHandler;
// Throws a null reference exception as there are no subscribers MessageArrived("Test message 2");
// Safely raising an event MessageHandler handler2 = MessageArrived; if (handler2 != null) { handler2("Safe message"); } }
static void MyHandler(string message) { System.Console.WriteLine(message); } }
delegate-id MessageHandler (str as string). end delegate.
class-id DelegatesEvents.
01 MessageArrived event type MessageHandler static.
method-id Main static. *> explicit delegate construction invoke new MessageHandler(MyHandler)
*> implicit delegate construction declare handler as type MessageHandler = method MyHandler
*> subscribe to an event attach method MyHandler to MessageArrived
*> raise the event invoke MessageArrived("Test message")
*> unsubscribe from the event detach method MyHandler from MessageArrived
*> Throws a null reference exception as there are no subscribers invoke MessageArrived("Test message 2")
*> Safely raising an event declare handler2 as type MessageHandler = MessageArrived if handler2 not equals null invoke handler1("Safe message") end-if
end method.
method-id MyHandler static (str as string). display str end method.
end class.
Delegate Sub MessageHandler(ByVal message As String)
Class DelegatesEvents
Shared Event MessageArrived As MessageHandler
Shared Sub Main() ' explicit delegate construction new MessageHandler(AddressOf MyHandler)
' implicit delegate construction Dim messageHandler As MessageHandler = AddressOf MyHandler
' subscribe to an event AddHandler MessageArrived, AddressOf MyHandler
' fire the event RaiseEvent MessageArrived("Test message")
' unsubscribe from the event RemoveHandler MessageArrived, AddressOf MyHandler
' Deosn't throw an exception, even when there are no subscribers RaiseEvent MessageArrived("Test message 2") End Sub
Shared Sub MyHandler(message As String) System.Console.WriteLine(message) End Sub
End Class
// Java has no concept of delegates or events. // Similar behaviour is typically achieved by using // anonymous inner classes instead.
Loops
C# COBOL VB.NET Java
Pre-test Loops: // no "until" keyword while (c < 10) { c++; }
for (c = 2; c <= 10; c += 2) { Console.WriteLine(c); }
Post-test Loop: do { c++; } while (c < 10);
Array or collection looping string[] names = {"Fred", "Sue", "Barney"}; foreach (string s in names) { Console.WriteLine(s); }
Breaking out of loops int i = 0; while (true) { if (i == 5) { break; } i++; }
Continue to next iteration for (i = 0; i < 5; i++) { if (i < 4) { continue; } Console.WriteLine(i); // Only prints 4 }
declare c as binary-long = 0
perform 10 times display "Again and " end-perform
*>Pre-test loops: perform until c >= 10 add 1 to c end-perform
perform varying c from 2 by 2 until c > 10 display c end-perform
perform varying c2 as binary-long from 2 by 2 until c2 > 10 display c end-perform
*>Post-test loops: set c = 0 perform with test after until c >= 10 add 1 to c end-perform
*> Varying
*>Array or collection looping declare names as string occurs any set content of names to ("Fred" "Sue" "Barney") perform varying s as string through names display s end-perform
*>Breaking out of loops: declare i as binary-long = 0 perform until exit if i = 5 exit perform end-if display i add 1 to i end-perform
*>Continue to next iteration: set i = 0 perform varying i from 0 by 1 until i >= 5 if i < 4 exit perform cycle end-if display i *>Only prints 4 end-perform
Pre-test Loops: While c < 10 c += 1 End While Do Until c = 10 c += 1 Loop
Do While c < 10 c += 1 Loop For c = 2 To 10 Step 2 Console.WriteLine(c) Next
Post-test Loops: Do c += 1 Loop While c < 10 Do c += 1 Loop Until c = 10
Array or collection looping Dim names As String() = {"Fred", "Sue", "Barney"} For Each s As String In names Console.WriteLine(s) Next
Breaking out of loops Dim i As Integer = 0 While (True) If (i = 5) Then Exit While End If i += 1 End While
Continue to next iteration For i = 0 To 4 If i < 4 Then Continue For End If Console.WriteLine(i) ' Only prints 4 Next
public class loops {
public static void main(String[] args) { int c = 0 ;
// Java has no direct equivalent to perform n times
// pre test loops // "while" means condition inverted from COBOL's "until" while ( c < 10); { c++; }
for (int c2 = 2 ; c2 > 10 ; c2 += 2) { System.out.println(c2); }
// Post test loops c = 0 ; do { c++; } while (c < 10 );
// looping through arrays or lists String names[] = {"Fred", "Sue", "Barney"}; for (String s : names) { System.out.println(s); }
// break out of loops int i = 0; while (true) { if (i == 5) break; System.out.println(i); i++; }
// Continue to next iteration: for (i = 0; i < 5 ; i++) { if (i < 4) continue; System.out.println(i); } }
}
Namespaces
C# COBOL VB.NET Java
namespace Harding.Compsci.Graphics { ... }
// or
namespace Harding { namespace Compsci { namespace Graphics { ... } } }
using Harding.Compsci.Graphics;
*> At the file level: $set ilnamespace(MicroFocus.COBOL.Examples)
*> The directive can also be set at project *> level to apply the namespace to all types in the project.
*> Alternatively, at the class level:
class-id MicroFocus.COBOL.Examples.MyClass. end class.
*> namespace import at file level: $set ilusing(MicroFocus.COBOL.Examples)
*> The directive can also be set at project *> level to apply the import to the entire project.
Namespace Harding.Compsci.Graphics ... End Namespace
' or
Namespace Harding Namespace Compsci Namespace Graphics ... End Namespace End Namespace End Namespace
Imports Harding.Compsci.Graphics
package MicroFocus.COBOL.Examples;
public class namespaces {
}
Operators
C# COBOL VB.NET Java
Comparison == < > <= >= !=
Arithmetic
- / % (mod) / (integer division if both operands are ints) Math.Pow(x, y)
Assignment = += -= *= /= %= &= |= ˆ= <<= >>= ++ --
Bitwise & | ˆ ˜ << >>
Logical && || & | ˆ!
//Note: && and || perform short-circuit logical evaluations String Concatenation
*> Comparison operators: *> = < > <= >= <> display (1 = 1) *> true
display (1 > 2) *> false
display (1 < 2) *> true
display (1 <= 1) *> true
display (1 >= 2) *> false
display (0 <> 1) *> true
*> Arithmetic operators, *> * / + - **
display ( (5 + 1) * (5 - 1) ) *> result 24 display ( 2 ** 3 ) *> result 8 display ( function mod (5 3) ) *> result 2
*> Local variable declarations declare a, b, c as binary-long declare d = "I'm a string" *> string type inferred from value
*> Assignment statements *> move, set, compute set a = 1 move 2 to b compute c = 3 * 6 set a = 3 * 6
*> Type operator declare mystr as string = "string" declare myobj as object = mystr display (myobj instance of string) *> true
*> Bitwise *> b-and, b-or, b-xor, b-not, b-left, b-right display (4 b-and 3) display (4 b-or 3) display (b-not 3) display (4 b-xor 3) display (4 b-left 1) *> shift left one place display (4 b-right 2) *> shift right two places
*> Logical *> and, or, not
display (true and false) *> false display (true or false) *> true display (not true) *> false
Comparison = < > <= >= <>
Arithmetic
- / Mod \ (integer division) ˆ (raise to a power)
Assignment = += -= *= /= = ˆ= <<= >>= &=
Bitwise And Or Xor Not << >>
Logical AndAlso OrElse And Or Xor Not
'Note: AndAlso and OrElse perform short-circuit logical evaluations String Concatenation &
public class operators {
public static void main(String[] args) { // Comparison operators // = < > <= >= != System.out.println(1 == 1); // true
System.out.println(1 > 2); // false
System.out.println(1 < 2); // true
System.out.println(1 <= 1); // true
System.out.println(1 >= 2); // false
System.out.println(0 != 1); // true
// Arithmetic operators // * / + - // No exponentiation operator - use static method Math.pow(); System.out.println( (5 + 1) * (5 - 1) ); // result 24 System.out.println( Math.pow(2, 3) ); // result 8 System.out.println( 5 % 3 ); // result 2
// Local variable declarations. int a, b, c; String d = "I'm a string" ; // no declaration type inference
// Assignment statements // all have same format in Java a = 1 ; b = 2; c = 3 * 6; a = 3 * 6;
// type operator String mystr = "string"; Object o = mystr; System.out.println(o instanceof String); // true
//Bitwise operations // & | ˆ ˜ << >> System.out.println (4 & 3); System.out.println (4 | 3); System.out.println (˜3); System.out.println (4 ˆ 3); System.out.println (4 << 1); // shift left one place System.out.println (4 >> 2); // shift right two places
// Logical // && ||!
System.out.println (true && false); // false System.out.println (true || false); // true System.out.println (!true); // false }
}
Program Structure
C# COBOL VB.NET Java
using System;
namespace Hello { public class HelloWorld { public static void Main(string[] args) { string name = "C#"; // See if an argument was passed from the command line if (args.Length == 1) { name = args[0]; } Console.WriteLine("Hello, " + name + "!"); } } }
class-id MicroFocus.Examples.HelloWorld. *> member variable 01 field1 binary-long.
method-id Main static(args as string occurs any). declare nam as string = "Bob" *> See if an argument was passed from the command line if size of args > 0 set nam to args[0] *> [] means 0 based index end-if end method.
end class.
Imports System Namespace Hello Class HelloWorld Overloads Shared Sub Main(ByVal args() As String) Dim name As String = "VB.NET" 'See if an argument was passed from the command line If args.Length = 1 Then name = args(0) End If Console.WriteLine("Hello, " & name & "!") End Sub End Class End Namespace End Class
public class program_structure { // Member variable private String field1 ;
public static void main(String[] args) { String nam = "Bob"; // See if an argument was passed from the command line if (args.length > 0) nam = args[0];
}
}
Properties
C# COBOL VB.NET Java
private int _size;
public int Size { get { return _size; } set { if (value < 0) { _size = 0; } else { _size = value; } } } foo.Size++;
class-id Things.
01 _size binary-long private. 01 ReadOnly binary-long property with no set value 3. 01 ReadWrite binary-long property.
property-id Size binary-long. *> Use property-value inside properties to *> pass the value in or out getter. set property-value to _size setter. if property-value < 0 set _size to 0 else set _size to property-value end-if end property.
method-id main static. declare foo = new Things() add 1 to foo::Size display foo::Size display foo::ReadOnly set foo::ReadWrite to 22 end method.
end class.
Private _size As Integer
Public Property Size() As Integer Get Return _size End Get Set (ByVal Value As Integer) If Value < 0 Then _size = 0 Else _size = Value End If End Set End Property
foo.Size += 1
// Java's properties are entirely convention based, // rather than being implemented by the system. // As a result they exist only as getter and setter methods.
class Properties { private int _size;
// no equivalent for shorthand properties
public int getSize() { return _size; }
public void setSize(int newSize) { _size = newSize; }
public void static main(String[] args) { Properties foo = new Properties() foo.setSize(foo.getSize() + 1); System.out.println(foo.getSize()); } }
Strings
C# COBOL VB.NET Java
// Escape sequences // \r // carriage-return // \n // line-feed // \t // tab // \ // backslash // " // quote
// String concatenation string co = "Micro Focus\t"; co += "Ltd"; // "Micro FocusLtd"
// Chars char letter = school[0]; // letter is H letter = Convert.ToChar(65); // letter is A letter = (char)65; // same thing char[] letters = "abc".ToCharArray(); // letters now holds new[] ('a', 'b', 'c');
// Verbatim string literal string msg = @"File is c:\temp\x.dat"; // same as string msg = "File is c:\temp\x.dat";
// String comparison string mascot = "Bisons"; if (mascot == "Bisons") // true if (mascot.Equals("Bisons")) // true if (mascot.ToUpper().Equals("BISONS")) // true if (mascot.CompareTo("Bisons") == 0) // true // String matching - No Like equivalent, use Regex // Substring s = mascot.Substring(2, 3)) // s is "son" // Replacement s = mascot.Replace("sons", "nomial")) // s is "Binomial" // Split string names = "Frank,Becky,Ethan,Braden"; string[] parts = names.Split(','); // One name in each slot // Date to string DateTime dt = new DateTime(1973, 10, 12); string s = dt.ToString("MMM dd, yyyy"); // Oct 12, 1973 // int to string int x = 2; string y = x.ToString(); // y is "2" // string to int int x = Convert.ToInt32("-5"); // x is - // Mutable string var buffer = new System.Text.StringBuilder("two "); buffer.Append("three "); buffer.Insert(0, "one "); buffer.Replace("two", "TWO"); Console.WriteLine(buffer); // Prints "one TWO three"
*> Escape sequences *> COBOL string literals don't have escape sequences, *> however you can specify strings as hex literals: *> x"0d" *> carriage-return *> x"0a" *> line-feed *> x"09" *> tab *> "" *> backslash *> """" *> quote
*> String concatenation declare co as string = "Micro Focus" & x"09". set co to co & "Ltd" *> "Micro FocusLtd"
*> Chars declare letter as character = co[0] *> letter is M set letter to 65 as character *> "A"
declare letters = as character occurs any = "abc".ToCharArray() *> letters now holds table of character ('a', 'b', 'c')
*> COBOL does not have verbatim string literals declare msg as string = "File is c:\temp\x.dat"
*> String comparison declare town = "Newbury"
*> this compares the value of *> strings rather than object references if town = "Newbury" display "true" end-if
*> Substring display town[1:3] *> displays "ewb"
*> Replacement *> set s to mascot::Replace("sons" "nomial") *> s is "Binomial" *> display s *> Split declare names = "Frank,Becky,Stephen,Helen". declare parts as list[string] declare p as binary-long create parts
*> TODO: Provide JVM/.NET CONDITIONALLY COMPILED EXAMPLE OF SPLIT/REPLACE
declare aParts as string occurs any declare nextPart as string perform until exit unstring names delimited by "," into nextPart with pointer p not on overflow exit perform write parts from nextPart end-unstring end-perform
' Special character constants (also accessible from ControlChars class) ' vbCr ' vbLf ' vbTab ' vbBack ' "" ' vbFormFeed ' vbVerticalTab ' vbCrLf, vbNewLine ' vbNullString
' String concatenation (use & or +) Dim co As String = "Micro Focus" & vbTab co = co & "Ltd" ' "Micro FocusLtd"
' Chars Dim letter As Char = co.Chars(0) ' letter is H letter = Convert.ToChar(65) ' letter is A letter = Chr(65) ' same thing
Dim letters = "abc".ToCharArray() ' letters now holds New Char(3) {"a"C, "b"C, "c"C}
' No verbatim string literals Dim msg As String = "File is c:\temp\x.dat"
' String comparison Dim mascot As String = "Bisons" If (mascot = "Bisons") Then ' true If (mascot.Equals("Bisons")) Then ' true If (mascot.ToUpper().Equals("BISONS")) Then ' true If (mascot.CompareTo("Bisons") = 0) Then ' true ' String matching with Like - Regex is more powerful If ("John 3:16" Like "Jo[Hh]? #:*") Then 'true ' Substring s = mascot.Substring(2, 3) ' s is "son" ' Replacement s = mascot.Replace("sons", "nomial") ' s is "Binomial" ' Split Dim names As String = "Frank,Becky,Ethan,Braden" Dim parts() As String = names.Split(","C) ' One name in each slot ' Date to string Dim dt As New DateTime(1973, 10, 12) Dim s As String = dt.ToString("MMM dd, yyyy") ' Oct 12, 1973 ' Integer to String Dim x As Integer = 2 Dim y As String = x.ToString() ' y is "2" ' String to Integer Dim x As Integer = Convert.ToInt32("-5") ' x is - ' Mutable string Dim buffer As New System.Text.StringBuilder("two ") buffer.Append("three ") buffer.Insert(0, "one ") buffer.Replace("two", "TWO") Console.WriteLine(buffer) ' Prints "one TWO three"
public class Strings {
public static void main(String[] args) { // Escape sequences: // "\n" // line-feed // "\t" // tab // "\" // backslash // """ // quote // string concatenation String co = "Micro Focus\t" ; co = co + "Ltd" ; // "Micro FocusLtd
char letter = co.charAt(0); letter = (char) 65; // "A"
// String literal String msg = "File is c:\temp\x.dat";
// String comparison String town = "Newbury"; if (town.equals("Newbury")) { System.out.println("true"); }
// Substring System.out.println(town.substring(1, 3)); //Displays "ewb"
// Split String names = "Frank,Becky,Stephen,Helen"; String[] parts = names.split(","); // split argument is a regex
Structs
C# COBOL VB.NET Java
struct StudentRecord { public string name; public float gpa;
public StudentRecord(string name, float gpa) { this.name = name; this.gpa = gpa; } } StudentRecord stu = new StudentRecord("Bob", 3.5f); StudentRecord stu2 = stu;
stu2.name = "Sue"; Console.WriteLine(stu.name); // Prints Bob Console.WriteLine(stu2.name); // Prints Sue
valuetype-id StudentRecord. 01 #name string public. 01 averageMark float-short public.
method-id new(studentName as string, averageMark as float-short). set self::name to studentName set self::averageMark to averageMark end method.
end valuetype.
class-id RecordClient.
method-id main static. declare stu = new StudentRecord("Bob", 3.5). declare stu2 as type StudentRecord set stu2 to stu set stu2::name to "Sue" display stu::name *> Prints Bob display stu2::name *> Prints Sue end method.
end class.
Structure StudentRecord Public name As String Public gpa As Single
Public Sub New(ByVal name As String, ByVal gpa As Single) Me.name = name Me.gpa = gpa End Sub End Structure
Dim stu As StudentRecord = New StudentRecord("Bob", 3.5) Dim stu2 As StudentRecord = stu
stu2.name = "Sue" Console.WriteLine(stu.name) ' Prints Bob Console.WriteLine(stu2.name) ' Prints Sue
// Java has no equivalent to .NET's general purpose structs.
