Source code

Option Explicit 
Public Sub main(ByJava args() As String) 
Dim a As Integer 
Dim s As String 
Dim b As Boolean 

a = a 
a = 0 + a 
a = a + 0 
a = 1 * a 
a = a * 1 
a = 3 * 2 

s = s 
s = s & "" 
s = "" & s 
s = "a" & "b" 

If False And b Then 
b = False And b 
b = b And False 
b = True Or b 
b = b Or True 
End If 

' resulting java byte code 
' does not show any optimization 
' int a = 0; 
' String s = ""; 
' a = a; 
' a = 0 + a; 
' a += 0; 
' a = 1 * a; 
' a *= 1; 
' a = 3 * 2; 
' s = s; 
' s = VBString.appendStrings(s, ""); 
' s = VBString.appendStrings("", s); 
' s = VBString.appendStrings("a", "b"); 


' If(False & b) 
' { 
' b = False & b; 
' b &= False; 
' b = True | b; 
' b |= True; 
' } 

' for comparison: 
' result of a Java compilation (JDK 1.5) 
' a = a; 
' a = 0 + a; 
' a = a + 0; 
' a = 1 * a; 
' a = a * 1; 
' a = 6; // 2 * 3 folded to 6; VB6 does the same 
' s = s; 
' s = (New StringBuilder()).append(s).append("").toString(); 
' s = (New StringBuilder()).append("").append(s).toString(); 
' s = "ab"; // "a" + "b" folded to "ab" 
' If(False & b) 
' { 
' b = False & b; 
' b &= False; 
' b = True | b; 
' b |= True; 
' } 

End Sub