ExpressionNode (JMRI API)

All Known Subinterfaces:

ExpressionNodeWithParameter

All Known Implementing Classes:

ExpressionNodeArithmeticOperator, ExpressionNodeArray, ExpressionNodeAssignmentOperator, ExpressionNodeBinaryOperator, ExpressionNodeBooleanOperator, ExpressionNodeComparingOperator, ExpressionNodeComplex, ExpressionNodeFalse, ExpressionNodeFloatingNumber, ExpressionNodeFunction, ExpressionNodeIdentifier, ExpressionNodeIncreaseDecreaseOperator, ExpressionNodeInstanceVariable, ExpressionNodeIntegerNumber, ExpressionNodeMap, ExpressionNodeMethod, ExpressionNodeString, ExpressionNodeTernaryOperator, ExpressionNodeTrue
```
public interface ExpressionNode
```
A parsed expression

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method	Description
`default void`	`assignValue(SymbolTable symbolTable, java.lang.Object value)`	Assign a value to this expression
`java.lang.Object`	`calculate(SymbolTable symbolTable)`	Calculate the expression
`default boolean`	`canBeAssigned()`	Can this expression be assigned a value?
`java.lang.String`	`getDefinitionString()`	Get a String that defines this expression node.

- Method Detail
  - calculate
```
java.lang.Object calculate(SymbolTable symbolTable)
                    throws JmriException
```
    Calculate the expression
    
    Parameters:
    
    symbolTable - the symbol table
    
    Returns:
    
    the result
    
    Throws:
    
    JmriException - if an error occurs
  - canBeAssigned
```
default boolean canBeAssigned()
```
    Can this expression be assigned a value?
    
    Returns:
    
    true if it's possible to assign a value to this expression, false otherwise
  - assignValue
```
default void assignValue(SymbolTable symbolTable,
                         java.lang.Object value)
                  throws JmriException
```
    Assign a value to this expression
    
    Parameters:
    
    symbolTable - the symbol table
    
    value - the value to assign
    
    Throws:
    
    JmriException - if an error occurs
  - getDefinitionString
```
java.lang.String getDefinitionString()
```
    Get a String that defines this expression node.
    
    Returns:
    
    the string