Java Basic Syntax Sheet:

Here are the tools you need in your Java Toolbox in your head. The red words cannot be changed. The green can be changed by you:

• Create a new program (like creating a new world with myfirstmethod in Alice):

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• create a variable
  • In Java: <type> <variable name> ;  example: _____________________
  • declare with correct type:
    • to hold 6 : ______________________,
    • to hold 6.5 : ______________________,
    • to hold 'a' :______________________,
    • to hold "abc": ______________________,
    • to hold something that can read from the screen: ______________________,
    • to hold true: ______________________,
      
  • In Alice: Click the new variable or new parameter button and choose number, String or boolean or other

   

  • change variable contents:
    • In Java: <variable name> = <some expression>; example:  __________________________
    • In Alice: Drag the variable to a blank line to create a set statement.
  • Say something on the screen: 
    • In Java: example: ______________________________________________________________________________
      • Remember: the semi-colon; capitalize System, use both parentheses;
        
      • Remember quotes around text and not around variable names
      • variations: printf and print
        
    • In Alice: Drag the say command over.
  • Work with methods
    • Define a method
      • add a method right before the class closing curly braces
      • a method header is immediately before the method's curly braces
        • ex: ______________________________________________________________________________
      • a method's parameter variables are created inside the parentheses (ex: in the statement above, int x is the parameter creation
      • a method's return type is defined before the method name (ex: in the statement above, double is the return type)
      • a method with a return type needs to end with a return statement.
      • a method with no return type (void) cannot have a return statement
    • Call a method:
      • for static methods you create: <method name> (any parms). ex: __________________________
      • for static methods that are not in your class: <class>.<method name> (any parms) ex: __________________________
      • for instance methods that are not in your class: <object>.<method name> (any parms) ex:__________________________
      • parameters must match in type and number
      • for methods that return a variable: set it = to something. ex: ____________________________________________________
    • In Alice
      • Define a method by clicking the new method button
      • Define a function by clicking the new function button and filling in the return statement
      • Call a method by dragging the method or functionfrom the character or world into your statement area and fill in the parameters
  • Create boolean expressions:
    
    • use when you want to save the result of a true/false question
    • use comparison operator:
      • greater than: ______________________,
      • less than: ______________________,
      • equal:______________________,
      • not equal: ______________________,
      • greater than or equal: ______________________,
      • less than or equal : ______________________,
    • use logical indicator
      • OR is ______________________,
      • AND is ______________________,
    • example: expression to be true x is between 5 and 10____________________________________
    • example: expression to be true when x isless than 5 or greater than 10____________________________________
    • exmple: a statement that sets a boolean to true: ____________________________________________________________