From 4fe7c7bd1eeb4ae954e750e521e6d72dc8ff5225 Mon Sep 17 00:00:00 2001 From: Yanbo Liang Date: Thu, 2 Jun 2016 11:10:13 -0500 Subject: [SPARK-15605][ML][EXAMPLES] Fix broken ML JavaDeveloperApiExample. ## What changes were proposed in this pull request? See [SPARK-15605](https://issues.apache.org/jira/browse/SPARK-15605) for the detail of this bug. This PR fix 2 major bugs in this example: * The java example class use Param ```maxIter```, it will fail when calling ```Param.shouldOwn```. We need add a public method which return the ```maxIter``` Object. Because ```Params.params``` use java reflection to list all public method whose return type is ```Param```, and invoke them to get all defined param objects in the instance. * The ```uid``` member defined in Java class will be initialized after Scala traits such as ```HasFeaturesCol```. So when ```HasFeaturesCol``` being constructed, they get ```uid``` with null, which will cause ```Param.shouldOwn``` check fail. so, here is my changes: * Add public method: ```public IntParam getMaxIterParam() {return maxIter;}``` * Use Java anonymous class overriding ```uid()``` to defined the ```uid```, and it solve the second problem described above. * To make the ```getMaxIterParam ``` can be invoked using java reflection, we must make the two class (MyJavaLogisticRegression and MyJavaLogisticRegressionModel) public. so I make them become inner public static class. ## How was this patch tested? Offline tests. Author: Yanbo Liang Closes #13353 from yanboliang/spark-15605. --- .../spark/examples/ml/JavaDeveloperApiExample.java | 240 --------------------- 1 file changed, 240 deletions(-) delete mode 100644 examples/src/main/java/org/apache/spark/examples/ml/JavaDeveloperApiExample.java (limited to 'examples/src') diff --git a/examples/src/main/java/org/apache/spark/examples/ml/JavaDeveloperApiExample.java b/examples/src/main/java/org/apache/spark/examples/ml/JavaDeveloperApiExample.java deleted file mode 100644 index 8971c0ac00..0000000000 --- a/examples/src/main/java/org/apache/spark/examples/ml/JavaDeveloperApiExample.java +++ /dev/null @@ -1,240 +0,0 @@ -/* - * Licensed to the Apache Software Foundation (ASF) under one or more - * contributor license agreements. See the NOTICE file distributed with - * this work for additional information regarding copyright ownership. - * The ASF licenses this file to You under the Apache License, Version 2.0 - * (the "License"); you may not use this file except in compliance with - * the License. You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ - -package org.apache.spark.examples.ml; - -import java.util.List; - -import com.google.common.collect.Lists; - -import org.apache.spark.api.java.JavaRDD; -import org.apache.spark.ml.classification.Classifier; -import org.apache.spark.ml.classification.ClassificationModel; -import org.apache.spark.ml.feature.LabeledPoint; -import org.apache.spark.ml.linalg.BLAS; -import org.apache.spark.ml.linalg.Vector; -import org.apache.spark.ml.linalg.Vectors; -import org.apache.spark.ml.param.IntParam; -import org.apache.spark.ml.param.ParamMap; -import org.apache.spark.ml.util.Identifiable$; -import org.apache.spark.sql.Dataset; -import org.apache.spark.sql.Row; -import org.apache.spark.sql.SparkSession; - - -/** - * A simple example demonstrating how to write your own learning algorithm using Estimator, - * Transformer, and other abstractions. - * This mimics {@link org.apache.spark.ml.classification.LogisticRegression}. - * - * Run with - * 
- * bin/run-example ml.JavaDeveloperApiExample
- *
- */ -public class JavaDeveloperApiExample { - - public static void main(String[] args) throws Exception { - SparkSession spark = SparkSession - .builder() - .appName("JavaDeveloperApiExample") - .getOrCreate(); - - // Prepare training data. - List localTraining = Lists.newArrayList( - new LabeledPoint(1.0, Vectors.dense(0.0, 1.1, 0.1)), - new LabeledPoint(0.0, Vectors.dense(2.0, 1.0, -1.0)), - new LabeledPoint(0.0, Vectors.dense(2.0, 1.3, 1.0)), - new LabeledPoint(1.0, Vectors.dense(0.0, 1.2, -0.5))); - Dataset training = spark.createDataFrame(localTraining, LabeledPoint.class); - - // Create a LogisticRegression instance. This instance is an Estimator. - MyJavaLogisticRegression lr = new MyJavaLogisticRegression(); - // Print out the parameters, documentation, and any default values. - System.out.println("MyJavaLogisticRegression parameters:\n" + lr.explainParams() + "\n"); - - // We may set parameters using setter methods. - lr.setMaxIter(10); - - // Learn a LogisticRegression model. This uses the parameters stored in lr. - MyJavaLogisticRegressionModel model = lr.fit(training); - - // Prepare test data. - List localTest = Lists.newArrayList( - new LabeledPoint(1.0, Vectors.dense(-1.0, 1.5, 1.3)), - new LabeledPoint(0.0, Vectors.dense(3.0, 2.0, -0.1)), - new LabeledPoint(1.0, Vectors.dense(0.0, 2.2, -1.5))); - Dataset test = spark.createDataFrame(localTest, LabeledPoint.class); - - // Make predictions on test documents. cvModel uses the best model found (lrModel). - Dataset results = model.transform(test); - double sumPredictions = 0; - for (Row r : results.select("features", "label", "prediction").collectAsList()) { - sumPredictions += r.getDouble(2); - } - if (sumPredictions != 0.0) { - throw new Exception("MyJavaLogisticRegression predicted something other than 0," + - " even though all coefficients are 0!"); - } - - spark.stop(); - } -} - -/** - * Example of defining a type of {@link Classifier}. - * - * Note: Some IDEs (e.g., IntelliJ) will complain that this will not compile due to - * {@link org.apache.spark.ml.param.Params#set} using incompatible return types. - * However, this should still compile and run successfully. - */ -class MyJavaLogisticRegression - extends Classifier { - - MyJavaLogisticRegression() { - init(); - } - - MyJavaLogisticRegression(String uid) { - this.uid_ = uid; - init(); - } - - private String uid_ = Identifiable$.MODULE$.randomUID("myJavaLogReg"); - - @Override - public String uid() { - return uid_; - } - - /** - * Param for max number of iterations - *

- * NOTE: The usual way to add a parameter to a model or algorithm is to include: - * - val myParamName: ParamType - * - def getMyParamName - * - def setMyParamName - */ - IntParam maxIter = new IntParam(this, "maxIter", "max number of iterations"); - - int getMaxIter() { return (Integer) getOrDefault(maxIter); } - - private void init() { - setMaxIter(100); - } - - // The parameter setter is in this class since it should return type MyJavaLogisticRegression. - MyJavaLogisticRegression setMaxIter(int value) { - return (MyJavaLogisticRegression) set(maxIter, value); - } - - // This method is used by fit(). - // In Java, we have to make it public since Java does not understand Scala's protected modifier. - public MyJavaLogisticRegressionModel train(Dataset dataset) { - // Extract columns from data using helper method. - JavaRDD oldDataset = extractLabeledPoints(dataset).toJavaRDD(); - - // Do learning to estimate the coefficients vector. - int numFeatures = oldDataset.take(1).get(0).features().size(); - Vector coefficients = Vectors.zeros(numFeatures); // Learning would happen here. - - // Create a model, and return it. - return new MyJavaLogisticRegressionModel(uid(), coefficients).setParent(this); - } - - @Override - public MyJavaLogisticRegression copy(ParamMap extra) { - return defaultCopy(extra); - } -} - -/** - * Example of defining a type of {@link ClassificationModel}. - * - * Note: Some IDEs (e.g., IntelliJ) will complain that this will not compile due to - * {@link org.apache.spark.ml.param.Params#set} using incompatible return types. - * However, this should still compile and run successfully. - */ -class MyJavaLogisticRegressionModel - extends ClassificationModel { - - private Vector coefficients_; - public Vector coefficients() { return coefficients_; } - - MyJavaLogisticRegressionModel(String uid, Vector coefficients) { - this.uid_ = uid; - this.coefficients_ = coefficients; - } - - private String uid_ = Identifiable$.MODULE$.randomUID("myJavaLogReg"); - - @Override - public String uid() { - return uid_; - } - - // This uses the default implementation of transform(), which reads column "features" and outputs - // columns "prediction" and "rawPrediction." - - // This uses the default implementation of predict(), which chooses the label corresponding to - // the maximum value returned by [[predictRaw()]]. - - /** - * Raw prediction for each possible label. - * The meaning of a "raw" prediction may vary between algorithms, but it intuitively gives - * a measure of confidence in each possible label (where larger = more confident). - * This internal method is used to implement [[transform()]] and output [[rawPredictionCol]]. - * - * @return vector where element i is the raw prediction for label i. - * This raw prediction may be any real number, where a larger value indicates greater - * confidence for that label. - * - * In Java, we have to make this method public since Java does not understand Scala's protected - * modifier. - */ - public Vector predictRaw(Vector features) { - double margin = BLAS.dot(features, coefficients_); - // There are 2 classes (binary classification), so we return a length-2 vector, - // where index i corresponds to class i (i = 0, 1). - return Vectors.dense(-margin, margin); - } - - /** - * Number of classes the label can take. 2 indicates binary classification. - */ - public int numClasses() { return 2; } - - /** - * Number of features the model was trained on. - */ - public int numFeatures() { return coefficients_.size(); } - - /** - * Create a copy of the model. - * The copy is shallow, except for the embedded paramMap, which gets a deep copy. - *

- * This is used for the default implementation of [[transform()]]. - * - * In Java, we have to make this method public since Java does not understand Scala's protected - * modifier. - */ - @Override - public MyJavaLogisticRegressionModel copy(ParamMap extra) { - return copyValues(new MyJavaLogisticRegressionModel(uid(), coefficients_), extra) - .setParent(parent()); - } -} -- cgit v1.2.3