Groovy for Domain-specific Languages - Second Edition

Chapter 12

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stmnt.statementLabel &&

stmnt.statementLabel == 'event'

}

boolean isNonEventBlock(Statement stmnt) {

stmnt instanceof ExpressionStatement &&

stmnt.expression instanceof ConstantExpression &&

stmnt.statementLabel &&

(stmnt.statementLabel == 'page' ||

stmnt.statementLabel == 'when' ||

stmnt.statementLabel == 'state')

}

Building the game engine pattern

Once the parser has completed its work, we should have a full representation of the
game engine in the GameEngineModel class. We next set about generating the classes
of the game engine from this model. The EnginePatternBuilder class takes over at
this point:

class EnginePatternBuilder {

def model

ModuleNode moduleNode

ClassNode classNode

String className

ClassNode contextClass

String sessionClassName

def sourceUnit

def compilationUnit

EnginePatternBuilder(ASTNode[] nodes, model, source, comp) {

this.model = model

moduleNode = nodes[0]

classNode = nodes[0].classes[0]

className = nodes[0].classes[0].nameWithoutPackage

this.sourceUnit = source

this.compilationUnit = comp

}

void buildEnginePattern() {

buildSessionClass()

updateClientClass()

buildPageClasses()

removeMethods()

}

........

}