in src/org/apache/pig/scripting/groovy/GroovyScriptEngine.java [136:426]
public void registerFunctions(String path, String namespace, PigContext pigContext) throws IOException {
if (!isInitialized) {
pigContext.addScriptJar(getJarPath(groovy.util.GroovyScriptEngine.class));
isInitialized = true;
}
try {
//
// Read file
//
Class c = gse.loadScriptByName(new File(path).toURI().toString());
//
// Keep track of initial/intermed/final methods of Albegraic UDFs
//
Map<String, Method[]> algebraicMethods = new HashMap<String, Method[]>();
//
// Keep track of accumulate/getValue/cleanup methods of Accumulator UDFs
//
Map<String, Method[]> accumulatorMethods = new HashMap<String, Method[]>();
//
// Loop over the methods
//
Method[] methods = c.getMethods();
for (Method method : methods) {
Annotation[] annotations = method.getAnnotations();
boolean isAccumulator = false;
if (annotations.length > 0) {
Schema schema = null;
String schemaFunction = null;
for (Annotation annotation : annotations) {
if (annotation.annotationType().equals(OutputSchema.class)) {
schema = Utils.getSchemaFromString(((OutputSchema) annotation).value());
} else if (annotation.annotationType().equals(OutputSchemaFunction.class)) {
schemaFunction = ((OutputSchemaFunction) annotation).value();
} else if (isAlgebraic(annotation)) {
String algebraic = null;
int idx = 0;
if (annotation.annotationType().equals(AlgebraicInitial.class)) {
//
// Check that method accepts a single Tuple as parameter.
//
Class<?>[] params = method.getParameterTypes();
if (1 != params.length || !Tuple.class.equals(params[0])) {
throw new IOException(path + ": methods annotated with @AlgebraicInitial MUST take a single groovy.lang.Tuple as parameter.");
}
if (!method.getReturnType().equals(Tuple.class) && !method.getReturnType().equals(Object[].class)) {
throw new IOException(path + ":" + method.getName()
+ " Algebraic UDF Initial method MUST return type groovy.lang.Tuple or Object[].");
}
algebraic = ((AlgebraicInitial) annotation).value();
idx = 0;
} else if (annotation.annotationType().equals(AlgebraicIntermed.class)) {
//
// Check that method accepts a single Tuple as parameter.
//
Class<?>[] params = method.getParameterTypes();
if (1 != params.length || !Tuple.class.equals(params[0])) {
throw new IOException(path + ": methods annotated with @AlgebraicIntermed MUST take a single groovy.lang.Tuple as parameter.");
}
if (!method.getReturnType().equals(Tuple.class) && !method.getReturnType().equals(Object[].class)) {
throw new IOException(path + ":" + method.getName()
+ " Algebraic UDF Intermed method MUST return type groovy.lang.Tuple or Object[].");
}
algebraic = ((AlgebraicIntermed) annotation).value();
idx = 1;
} else {
//
// Check that method accepts a single Tuple as parameter.
//
Class<?>[] params = method.getParameterTypes();
if (1 != params.length || !Tuple.class.equals(params[0])) {
throw new IOException(path + ": methods annotated with @AlgebraicFinal MUST take a single groovy.lang.Tuple as parameter.");
}
algebraic = ((AlgebraicFinal) annotation).value();
idx = 2;
}
Method[] algmethods = algebraicMethods.get(algebraic);
if (null == algmethods) {
algmethods = new Method[3];
algebraicMethods.put(algebraic, algmethods);
}
if (null != algmethods[idx]) {
throw new IOException(path + ": Algebraic UDF '" + algebraic + "' already has an "
+ annotation.annotationType().getSimpleName() + " method defined ('" + algmethods[idx] + "')");
}
algmethods[idx] = method;
} else if (isAccumulator(annotation)) {
String accumulator = null;
int idx = 0;
if (annotation.annotationType().equals(AccumulatorAccumulate.class)) {
//
// Check that method accepts a single Tuple as parameter.
//
Class<?>[] params = method.getParameterTypes();
if (1 != params.length || !Tuple.class.equals(params[0])) {
throw new IOException(path + ": methods annotated with @AccumulatorAccumulate MUST take a single groovy.lang.Tuple as parameter.");
}
accumulator = ((AccumulatorAccumulate) annotation).value();
idx = 0;
} else if (annotation.annotationType().equals(AccumulatorGetValue.class)) {
//
// Check that method does not accept any parameters.
//
Class<?>[] params = method.getParameterTypes();
if (0 != params.length) {
throw new IOException(path + ": methods annotated with @AccumulatorGetValue take no parameters.");
}
accumulator = ((AccumulatorGetValue) annotation).value();
isAccumulator = true;
idx = 1;
} else if (annotation.annotationType().equals(AccumulatorCleanup.class)) {
//
// Check that method does not accept any parameters.
//
Class<?>[] params = method.getParameterTypes();
if (0 != params.length) {
throw new IOException(path + ": methods annotated with @AccumulatorCleanup take no parameters and return void.");
}
accumulator = ((AccumulatorCleanup) annotation).value();
idx = 2;
}
Method[] accumethods = accumulatorMethods.get(accumulator);
if (null == accumethods) {
accumethods = new Method[3];
accumulatorMethods.put(accumulator, accumethods);
}
if (null != accumethods[idx]) {
throw new IOException(path + ": Accumulator UDF '" + accumulator + "' already has an "
+ annotation.annotationType().getSimpleName() + " method defined ('" + accumethods[idx] + "')");
}
accumethods[idx] = method;
}
}
//
// Only register functions which have an output schema declared
//
if (null == schema && null == schemaFunction) {
LOG.info(path
+ ": Only methods annotated with @OutputSchema or @OutputSchemaFunction (but not with @AccumulatorGetValue are exposed to Pig, skipping method '"
+ method.getName() + "'");
continue;
}
//
// Only one of OutputSchema / OutputSchemaFunction can be defined
//
if (null != schema && null != schemaFunction) {
LOG.info("Annotation @OutputSchemaFunction has precedence over @OutputSchema for method '" + method.getName() + "'");
}
//
// Register methods annotated with 'OutputSchema' or
// 'OutputSchemaFunction, unless they are accumulators' getValue
// methods
//
if (!isAccumulator) {
namespace = (namespace == null) ? "" : namespace;
FuncSpec spec = new FuncSpec(GroovyEvalFuncObject.class.getCanonicalName() + "('" + path + "','" + namespace
+ "','" + method.getName() + "')");
pigContext.registerFunction(("".equals(namespace) ? "" : (namespace + NAMESPACE_SEPARATOR)) + method.getName(),
spec);
LOG.info(path + ": Register Groovy UDF: " + ("".equals(namespace) ? "" : (namespace + NAMESPACE_SEPARATOR))
+ method.getName());
}
}
}
//
// Now register algebraic methods
//
for (String algebraic : algebraicMethods.keySet()) {
Method[] algmethods = algebraicMethods.get(algebraic);
if (null == algmethods[0]) {
throw new IOException(path + ": Algebratic UDF '" + algebraic + "' does not have an Initial method defined.");
} else if (null == algmethods[1]) {
throw new IOException(path + ": Algebratic UDF '" + algebraic + "' does not have an Intermed method defined.");
} else if (null == algmethods[2]) {
throw new IOException(path + ": Algebratic UDF '" + algebraic + "' does not have a Final method defined.");
}
//
// Retrieve schema of 'Final' method
//
String className = null;
Class<?> returnType = algmethods[2].getReturnType();
if (returnType.equals(Tuple.class) || returnType.equals(Object[].class)
|| returnType.equals(org.apache.pig.data.Tuple.class)) {
className = TupleGroovyAlgebraicEvalFunc.class.getName();
} else if (returnType.equals(List.class) || returnType.equals(DataBag.class)) {
className = DataBagGroovyAlgebraicEvalFunc.class.getName();
} else if (returnType.equals(org.joda.time.DateTime.class)) {
className = DateTimeGroovyAlgebraicEvalFunc.class.getName();
} else if (returnType.equals(Boolean.class) || returnType.equals(boolean.class)) {
className = BooleanGroovyAlgebraicEvalFunc.class.getName();
} else if (returnType.equals(byte[].class) || returnType.equals(DataByteArray.class)) {
className = DataByteArrayGroovyAlgebraicEvalFunc.class.getName();
} else if (returnType.equals(String.class)) {
className = ChararrayGroovyAlgebraicEvalFunc.class.getName();
} else if (returnType.equals(Double.class) || returnType.equals(double.class) || returnType.equals(BigDecimal.class)) {
className = DoubleGroovyAlgebraicEvalFunc.class.getName();
} else if (returnType.equals(Float.class) || returnType.equals(float.class)) {
className = FloatGroovyAlgebraicEvalFunc.class.getName();
} else if (returnType.equals(Byte.class) || returnType.equals(byte.class) || returnType.equals(Short.class)
|| returnType.equals(short.class) || returnType.equals(Integer.class) || returnType.equals(int.class)) {
className = IntegerGroovyAlgebraicEvalFunc.class.getName();
} else if (returnType.equals(Long.class) || returnType.equals(long.class) || returnType.equals(BigInteger.class)) {
className = LongGroovyAlgebraicEvalFunc.class.getName();
} else if (returnType.equals(Map.class)) {
className = MapGroovyAlgebraicEvalFunc.class.getName();
} else if (returnType.equals(BigDecimal.class)) {
className = BigDecimalGroovyAlgebraicEvalFunc.class.getName();
} else if (returnType.equals(BigInteger.class)) {
className = BigIntegerGroovyAlgebraicEvalFunc.class.getName();
} else {
throw new RuntimeException(path + ": Unknown return type for Algebraic UDF '" + algebraic + "'");
}
FuncSpec spec = new FuncSpec(className + "('" + path + "','" + namespace + "','" + algebraic + "','"
+ algmethods[0].getName() + "','" + algmethods[1].getName() + "','" + algmethods[2].getName() + "')");
pigContext.registerFunction(("".equals(namespace) ? "" : (namespace + NAMESPACE_SEPARATOR)) + algebraic, spec);
LOG.info("Register Groovy Algebraic UDF: " + ("".equals(namespace) ? "" : (namespace + NAMESPACE_SEPARATOR))
+ algebraic);
}
//
// Now register Accumulator UDFs
//
for (String accumulator : accumulatorMethods.keySet()) {
Method[] accumethods = accumulatorMethods.get(accumulator);
if (null == accumethods[0]) {
throw new IOException(path + ": Accumulator UDF '" + accumulator + "' does not have an Accumulate method defined.");
} else if (null == accumethods[1]) {
throw new IOException(path + ": Accumulator UDF '" + accumulator + "' does not have a GetValue method defined.");
} else if (null == accumethods[2]) {
throw new IOException(path + ": Accumulator UDF '" + accumulator + "' does not have a Cleanup method defined.");
}
FuncSpec spec = new FuncSpec(GroovyAccumulatorEvalFunc.class.getName() + "('" + path + "','" + namespace + "','"
+ accumulator + "','" + accumethods[0].getName() + "','" + accumethods[1].getName() + "','"
+ accumethods[2].getName() + "')");
pigContext.registerFunction(("".equals(namespace) ? "" : (namespace + NAMESPACE_SEPARATOR)) + accumulator, spec);
LOG.info("Register Groovy Accumulator UDF: " + ("".equals(namespace) ? "" : (namespace + NAMESPACE_SEPARATOR))
+ accumulator);
}
} catch (ResourceException re) {
throw new IOException(re);
} catch (ScriptException se) {
throw new IOException(se);
}
}