Java tutorial
/* * Licensed to the Ted Dunning under one or more contributor license * agreements. See the NOTICE file that may be * distributed with this work for additional information * regarding copyright ownership. Ted Dunning 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 com.mapr.synth.samplers; import com.fasterxml.jackson.annotation.JsonCreator; import com.fasterxml.jackson.annotation.JsonProperty; import com.fasterxml.jackson.databind.JsonNode; import com.fasterxml.jackson.databind.node.TextNode; /** * Glue together elements of a list as strings. Should normally only be done with a list of strings. * * Thread safe for sampling */ public class JoinSampler extends FieldSampler { private FieldSampler delegate; private String separator = ","; @JsonCreator public JoinSampler(@JsonProperty("value") FieldSampler delegate) { this.delegate = delegate; } @SuppressWarnings("UnusedDeclaration") public void setSeparator(String separator) { this.separator = separator; } @Override public JsonNode sample() { JsonNode value = delegate.sample(); StringBuilder r = new StringBuilder(); String separator = ""; for (JsonNode component : value) { r.append(separator); r.append(component.asText()); separator = this.separator; } return new TextNode(r.toString()); } }