com.google.template.soy.jbcsrc.restricted

Class LocalVariable

java.lang.Object

com.google.template.soy.jbcsrc.restricted.BytecodeProducer

com.google.template.soy.jbcsrc.restricted.Expression

com.google.template.soy.jbcsrc.restricted.LocalVariable

public final class LocalVariable
extends Expression

A local variable representation.

This does nothing to enforce required constraints, e.g.:

• This does not ensure that start() and end() are valid and exist in the method.
• This does not ensure that the index is otherwise unused and that only one variable is active at a time with the index.

Note: This class does not attempt to make use of the convenience methods on generator adapter such as CodeBuilder#newLocal(Type) or CodeBuilder#loadArg(int) that make it easier to work with local variables (and calculating local variable indexes). Instead we push this responsibility onto our caller. This is because CodeBuilder doesn't make it possible to generate local variable debugging tables in this case (e.g. there is no way to map a method parameter index to a local variable index).

Nested Class Summary

Nested classes/interfaces inherited from class com.google.template.soy.jbcsrc.restricted.Expression

Expression.Feature, Expression.Features

Field Summary

Fields inherited from class com.google.template.soy.jbcsrc.restricted.BytecodeProducer

location

Method Summary

Modifier and Type	Method and Description
LocalVariable	asCheap() Returns an equivalent expression where Expression.isCheap() returns true.
LocalVariable	asNonNullable() Returns an equivalent expression where Expression.isNonNullable() returns true.
static LocalVariable	createLocal(String name, int index, org.objectweb.asm.Type type, org.objectweb.asm.Label start, org.objectweb.asm.Label end)
static LocalVariable	createThisVar(TypeInfo owner, org.objectweb.asm.Label start, org.objectweb.asm.Label end)
protected void	doGen(CodeBuilder mv) Generate code to evaluate the expression.
org.objectweb.asm.Label	end() A label defining the latest point at which this variable is defined.
protected void	extraToStringProperties(com.google.common.base.MoreObjects.ToStringHelper helper) Subclasses can override this to supply extra properties for the toString method.
int	index()
org.objectweb.asm.Label	start() A label defining the earliest point at which this variable is defined.
Statement	store(Expression expr) Return a Statement that stores the value of the given expression into this variable.
Statement	store(Expression expr, org.objectweb.asm.Label firstVarInstruction) Return a Statement that stores the value of the given expression into this variable.
void	tableEntry(CodeBuilder mv) Write a local variable table entry for this variable.
String	variableName() The name of the variable, ends up in debugging tables.

Methods inherited from class com.google.template.soy.jbcsrc.restricted.Expression

areAllCheap, areAllCheap, asNullable, checkAssignableTo, checkAssignableTo, checkedCast, checkedCast, checkTypes, features, invoke, invokeVoid, isCheap, isNonNullable, labelEnd, labelStart, resultType, toStatement, toString, withSourceLocation

Methods inherited from class com.google.template.soy.jbcsrc.restricted.BytecodeProducer

gen, trace

Methods inherited from class java.lang.Object

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

Method Detail

createThisVar

public static LocalVariable createThisVar(TypeInfo owner,
                                          org.objectweb.asm.Label start,
                                          org.objectweb.asm.Label end)

createLocal

public static LocalVariable createLocal(String name,
                                        int index,
                                        org.objectweb.asm.Type type,
                                        org.objectweb.asm.Label start,
                                        org.objectweb.asm.Label end)

variableName

public String variableName()

The name of the variable, ends up in debugging tables.

index

public int index()

start

public org.objectweb.asm.Label start()

A label defining the earliest point at which this variable is defined.

end

public org.objectweb.asm.Label end()

A label defining the latest point at which this variable is defined.

asCheap

public LocalVariable asCheap()

Description copied from class: Expression

Returns an equivalent expression where Expression.isCheap() returns true.

Overrides:

asCheap in class Expression

asNonNullable

public LocalVariable asNonNullable()

Description copied from class: Expression

Returns an equivalent expression where Expression.isNonNullable() returns true.

Overrides:

asNonNullable in class Expression

tableEntry

public void tableEntry(CodeBuilder mv)

Write a local variable table entry for this variable. This informs debuggers about variable names, types and lifetime.

doGen

protected void doGen(CodeBuilder mv)

Description copied from class: Expression

Generate code to evaluate the expression.

The generated code satisfies the invariant that the top of the runtime stack will contain a value with this Expression.resultType() immediately after evaluation of the code.

Specified by:

doGen in class Expression

store

public Statement store(Expression expr)

Return a Statement that stores the value of the given expression into this variable.

store

public Statement store(Expression expr,
                       org.objectweb.asm.Label firstVarInstruction)

Return a Statement that stores the value of the given expression into this variable.

Parameters:

expr - The expression to store

firstVarInstruction - A label to use to mark the store instruction

extraToStringProperties

protected void extraToStringProperties(com.google.common.base.MoreObjects.ToStringHelper helper)

Description copied from class: Expression

Subclasses can override this to supply extra properties for the toString method.

Overrides:

extraToStringProperties in class Expression