ExecutionContext

Package: com.hypixel.hytale.server.npc.util.expression

public class ExecutionContext

Stack-based virtual machine that executes compiled expression instruction sequences. Maintains an operand stack of Operand slots (auto-growing by increments of 8), a current Scope, and optional combat config / interaction variable context. Provides pre-defined static Instruction constants for all arithmetic, logical, bitwise, and comparison operators, plus factory methods for generating PUSH, READ, CALL, and PACK instructions.

Constants (Instruction Singletons)

Name	Operation
UNARY_PLUS	No-op (identity).
UNARY_MINUS	Negate top number.
LOGICAL_NOT	Negate top boolean.
BITWISE_NOT	Bitwise complement of top int.
EXPONENTIATION	pow(a, b)
REMAINDER	a % b
DIVIDE	a / b
MULTIPLY	a * b
MINUS	a - b
PLUS	a + b
GREATER_EQUAL, GREATER, LESS_EQUAL, LESS	Numeric comparisons.
NOT_EQUAL, EQUAL	Numeric equality.
NOT_EQUAL_BOOL, EQUAL_BOOL	Boolean equality.
BITWISE_AND, BITWISE_XOR, BITWISE_OR	Bitwise integer ops.
LOGICAL_AND, LOGICAL_OR	Short-circuit boolean ops.

Fields

Modifier	Type	Name
public static final	int	STACK_GROW_INCREMENT
protected	Scope	scope
protected	Operand[]	operandStack
protected	int	stackTop
protected	ValueType	lastPushedType
protected	String	combatConfig
protected	Map<String, String>	interactionVars

Constructors

Signature
public ExecutionContext(Scope scope)
public ExecutionContext()

Execution Methods

Modifier	Return Type	Signature
public	ValueType	execute(@Nonnull List<Instruction> instructions, Scope scope)
public	ValueType	execute(@Nonnull List<Instruction> instructions)
public	ValueType	execute(@Nonnull Instruction[] instructions, Scope scope)
public	ValueType	execute(@Nonnull Instruction[] instructions)

Stack Operations

Modifier	Return Type	Signature
public	void	push(String value)
public	void	push(double value)
public	void	push(int value)
public	void	push(boolean value)
public	void	push(String[] value)
public	void	push(double[] value)
public	void	push(boolean[] value)
public	void	pushEmptyArray()
public	double	popNumber()
public	int	popInt()
public	String	popString()
public	boolean	popBoolean()
public	double[]	popNumberArray()
@Nullable public	String[]	popStringArray()
public	boolean[]	popBooleanArray()
public	String	popAsString()
public	void	popPush(String value, int popCount)
public	void	popPush(double value, int popCount)
public	void	popPush(int value, int popCount)
public	void	popPush(boolean value, int popCount)
public	void	popPush(String[] value, int popCount)
public	void	popPush(double[] value, int popCount)
public	void	popPush(boolean[] value, int popCount)
public	void	popPushEmptyArray(int popCount)

Instruction Generation (Static Factories)

Modifier	Return Type	Signature
@Nonnull public static	Instruction	genPUSH(String value)
@Nonnull public static	Instruction	genPUSH(double value)
@Nonnull public static	Instruction	genPUSH(boolean value)
@Nonnull public static	Instruction	genPUSH(String[] value)
@Nonnull public static	Instruction	genPUSH(double[] value)
@Nonnull public static	Instruction	genPUSH(boolean[] value)
@Nonnull public static	Instruction	genPUSHEmptyArray()
@Nonnull public static	Instruction	genREAD(String ident, @Nonnull ValueType type, @Nullable Scope scope)
@Nonnull public static	Instruction	genCALL(String ident, int numArgs, @Nullable Scope scope)
@Nonnull public static	Instruction	genNumberPACK(int size)
@Nonnull public static	Instruction	genStringPACK(int size)
@Nonnull public static	Instruction	genBooleanPACK(int size)
@Nonnull public static	Instruction	genPACK(@Nonnull ValueType arrayType, int size)

Inner Types

Instruction (functional interface)

@FunctionalInterface
public interface Instruction {
    void execute(ExecutionContext var1);
}

A single executable step in a compiled expression. All operator constants, PUSH/READ/CALL/PACK generators, and user-defined functions implement this interface.

Operand (static inner class)

public static class Operand

Mutable value holder on the operand stack. Stores one value of any supported type (string, number, bool, numberArray, stringArray, boolArray) plus a ValueType discriminant. Reused across evaluations to minimize allocation.

Related Types

• Expression — high-level compile/execute entry point
• Scope — variable/function provider
• ValueType — type discriminant