Package com.singularsys.jep.misc.nullwrapper

Class NullWrappedOperatorTable

java.lang.Object

com.singularsys.jep.EmptyOperatorTable

com.singularsys.jep.OperatorTable2

com.singularsys.jep.misc.nullwrapper.NullWrappedOperatorTable

All Implemented Interfaces:

JepComponent, OperatorTableI, Serializable

public class NullWrappedOperatorTable
extends OperatorTable2

An operator table where the operators generally return null if either argument is null. The table can optionally add a null-safe equals operator <=> which acts like equals but returns 1 if both arguments are null.

Since:

3.4

Author:

Richard Morris

See Also:

• NullSafeEquals
• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	NullWrappedOperatorTable.NullWrapperOperators	Key for the one operator NullSafeEquals added by the table.

Nested classes/interfaces inherited from class com.singularsys.jep.OperatorTable2

OperatorTable2.BasicOperators, OperatorTable2.PsudoOperators, OperatorTable2.SpecialOperators

Nested classes/interfaces inherited from class com.singularsys.jep.EmptyOperatorTable

EmptyOperatorTable.OperatorKey

Field Summary

Fields

Modifier and Type	Field	Description
protected NullWrappedFunctionFactory	factory
protected boolean	hasNullSafeEquals
protected OperatorTable2	root

Constructor Summary

Constructors

Modifier	Constructor	Description
	NullWrappedOperatorTable(OperatorTable2 root, boolean hasNullSafeEquals)	Create a new operator table which wraps all the existing operators in the original table.
	NullWrappedOperatorTable(OperatorTable2 root, NullWrappedFunctionFactory factory, boolean hasNullSafeEquals)	A table where a specific NullWrapperFunctionFactory is defined.
protected	NullWrappedOperatorTable(Map<EmptyOperatorTable.OperatorKey,Operator> map)

Method Summary

Modifier and Type	Method	Description
OperatorTableI	shallowCopy()	Create a new version of this OperatorTable.

Methods inherited from class com.singularsys.jep.OperatorTable2

getAdd, getAnd, getAssign, getCross, getDivide, getDot, getEle, getEQ, getGE, getGT, getLE, getList, getLT, getMod, getMultiply, getNE, getNop, getNot, getOr, getPower, getRange, getSubtract, getUDivide, getUMinus, getUPlus

Methods inherited from class com.singularsys.jep.EmptyOperatorTable

addOperator, addOperator, addOperator, appendOperator, appendOperator, entrySet, getKey, getLightWeightInstance, getNumOps, getOperator, getOperatorMap, getOperators, getOperatorsByName, getOperatorsBySymbol, init, insertOperator, insertOperator, keySet, removeOperator, removeOperator, replaceOperator, replaceOperator, setBinaryInverseOp, setDistributiveOver, setGroupOperatorRelations, setGroupOperatorRelations, setInverseOp, setPrecedenceTable, setRootOp, setStandardOperatorRelations, threadSafeMapCopy, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details

root

protected OperatorTable2 root

factory

protected NullWrappedFunctionFactory factory

hasNullSafeEquals

protected boolean hasNullSafeEquals

Constructor Details

NullWrappedOperatorTable

public NullWrappedOperatorTable(OperatorTable2 root,
 boolean hasNullSafeEquals)

Create a new operator table which wraps all the existing operators in the original table. Calls NullWrappedFunctionFactory.getWrappedFunction(PostfixMathCommandI) to find the appropriate PFMC for each operator.

Parameters:

root - the original operator table

hasNullSafeEquals - if true adds a NullSafeEquals operator "<=>" to the table

NullWrappedOperatorTable

public NullWrappedOperatorTable(OperatorTable2 root,
 NullWrappedFunctionFactory factory,
 boolean hasNullSafeEquals)

A table where a specific NullWrapperFunctionFactory is defined.

Parameters:

root -

factory -

hasNullSafeEquals -

Since:

Jep 3.5

NullWrappedOperatorTable

protected NullWrappedOperatorTable(Map<EmptyOperatorTable.OperatorKey,Operator> map)

Method Details

shallowCopy

public OperatorTableI shallowCopy()

Description copied from class: EmptyOperatorTable

Create a new version of this OperatorTable. Operators are copied into new table. However, Operators whose pfmc implement JepComponent are duplicated. This means the table could be used in a separate thread without problem. Subclasses should override with method to return a table of the correct type, a typical implementation would be

    @Override
    public OperatorTableI shallowCopy() {
        Map<OperatorKey, Operator> map = this.threadSafeMapCopy();
        return new MyOperatorTable(map);
    }
 

using the EmptyOperatorTable.threadSafeMapCopy() method to return a copy of the map of operators and a constructor taking this map which uses the EmptyOperatorTable(Map) constructor.

Specified by:

shallowCopy in interface OperatorTableI

Overrides:

shallowCopy in class OperatorTable2

Returns:

a new Table