Examples with ClassGenerator org.neo4j.codegen.ClassGenerator used on opensource projects

Example 6 with ClassGenerator

use of org.neo4j.codegen.ClassGenerator in project neo4j by neo4j.

the class ProcedureCompilation method generateAggregator.

private static Class<?> generateAggregator(CodeGenerator codeGenerator, Method update, Method result, UserFunctionSignature signature) {
    assert update.getDeclaringClass().equals(result.getDeclaringClass());
    Class<?> userAggregatorClass = update.getDeclaringClass();
    ClassHandle handle;
    try (ClassGenerator generator = codeGenerator.generateClass(PACKAGE, "Aggregator" + userAggregatorClass.getSimpleName() + System.nanoTime(), UserAggregator.class)) {
        FieldReference aggregator = generator.field(userAggregatorClass, "aggregator");
        FieldReference context = generator.field(Context.class, "ctx");
        // constructor
        try (CodeBlock constructor = generator.generateConstructor(param(userAggregatorClass, "aggregator"), param(Context.class, "ctx"))) {
            constructor.expression(invokeSuper(OBJECT));
            constructor.put(constructor.self(), aggregator, constructor.load("aggregator"));
            constructor.put(constructor.self(), context, constructor.load("ctx"));
        }
        // update
        try (CodeBlock block = generator.generate(AGGREGATION_UPDATE)) {
            block.tryCatch(onSuccess -> onSuccess.expression(invoke(get(onSuccess.self(), aggregator), methodReference(update), parameters(onSuccess, update, get(onSuccess.self(), context)))), onError -> onError(onError, format("function `%s`", signature.name())), param(Throwable.class, "T"));
        }
        // result
        try (CodeBlock block = generator.generate(AGGREGATION_RESULT)) {
            block.tryCatch(onSuccess -> onSuccess.returns(toAnyValue(invoke(get(onSuccess.self(), aggregator), methodReference(result)), result.getReturnType(), get(onSuccess.self(), context))), onError -> onError(onError, format("function `%s`", signature.name())), param(Throwable.class, "T"));
        }
        handle = generator.handle();
    }
    try {
        return handle.loadClass();
    } catch (CompilationFailureException e) {
        // We are being called from a lambda so it'll have to do with runtime exceptions here
        throw new RuntimeException("Failed to generate iterator", e);
    }
}