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POAfter retrieving JSON elements dynamically, how to remove duplicates values? Arraylist? HashMap?
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copied!<p>I have suggestion saying storing the elements in arraylist then do a comparison, and i also hear people suggesting to use HashMap. However, i am very very new to Java, i got no idea what is arraylist and what is hashmap. Any kind soul to lead me?</p> <p>My json file:</p> <pre><code>{"rel": "IsA", "weight": 0.5, "dataset": "/d/dbpedia/en", "sources": ["/s/dbpedia/3.7"], "id": "914e6775fd79d660bacf22ec699568e6694da3e8", "features": ["america_beautiful IsA -", "america_beautiful - national_anthem", "- IsA national_anthem"], "end": "national_anthem", "license": "/l/CC/By-SA", "uri": "/a/[IsA/,america_beautiful/,national_anthem/]", "start": "america_beautiful", "context": "/ctx/all", "surfaceText": null} {"rel": "PartOf", "weight": 0.5, "dataset": "/d/dbpedia/en", "sources": ["/s/dbpedia/3.7"], "id": "a2c3ddf6b6237156dbeac84eea2801d35a9562d4", "features": ["ankara PartOf -", "ankara - central_anatolia_region", "- PartOf central_anatolia_region"], "end": "central_anatolia_region", "license": "/l/CC/By-SA", "uri": "/a/[PartOf/,ankara/,central_anatolia_region/]", "start": "ankara", "context": "/ctx/all", "surfaceText": null} {"rel": "AtLocation", "weight": 0.5, "dataset": "/d/dbpedia/en", "sources": ["/s/dbpedia/3.7"], "id": "ec1914bfb0606c36376fbbcd316e5666022e2469", "features": ["apple_inc AtLocation -", "apple_inc - unite_state", "- AtLocation unite_state"], "end": "unite_state", "license": "/l/CC/By-SA", "uri": "/a/[AtLocation/,apple_inc/,unite_state/]", "start": "apple_inc", "context": "/ctx/all", "surfaceText": null} {"rel": "AtLocation", "weight": 0.5, "dataset": "/d/dbpedia/en", "sources": ["/s/dbpedia/3.7"], "id": "0209765bf7185615ef242513f61ca0f61efe2a04", "features": ["audi AtLocation -", "audi - curitiba", "- AtLocation curitiba"], "end": "curitiba", "license": "/l/CC/By-SA", "uri": "/a/[AtLocation/,audi/,curitiba/]", "start": "audi", "context": "/ctx/all", "surfaceText": null} {"rel": "AtLocation", "weight": 0.5, "dataset": "/d/dbpedia/en", "sources": ["/s/dbpedia/3.7"], "id": "5158d1cfce728efb3e42840d166ec06153a3d77d", "features": ["audi AtLocation -", "audi - ingolstadt", "- AtLocation ingolstadt"], "end": "unite_state", "license": "/l/CC/By-SA", "uri": "/a/[AtLocation/,audi/,ingolstadt/]", "start": "audi", "context": "/ctx/all", "surfaceText": null} </code></pre> <p>My java file:</p> <pre><code>package com.infinitegraph.samples.hellograph; // Import all InfiniteGraph packages import java.io.BufferedReader; import java.io.FileReader; import java.io.IOException; import com.infinitegraph.*; import org.json.simple.JSONObject; import org.json.simple.parser.JSONParser; import org.json.simple.parser.ParseException; // Import SLF4J logging packages import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.infinitegraph.BaseVertex; import java.util.HashMap; import java.util.ArrayList; public class HelloGraph { public static void main(String[] args) { BufferedReader br = null; JSONParser parser = new JSONParser(); // Set up logging for the HelloGraph class Logger logger = LoggerFactory.getLogger(HelloGraph.class); // Create null transaction, null graph database instance Transaction tx = null; GraphDatabase helloGraphDB = null; // Name for graph database and property file String graphDbName = "HelloGraph"; String propertiesFileName = "HelloGraph.properties"; try { try { // Delete graph database if it already exists GraphFactory.delete(graphDbName, propertiesFileName); } catch (StorageException sE) { logger.info(sE.getMessage()); } // HINT: Add code to create graph database and its contents // Create graph database logger.info("> Creating graph database ..."); GraphFactory.create(graphDbName, propertiesFileName); // Open graph database logger.info("> Opening graph database ..."); helloGraphDB = GraphFactory.open(graphDbName, propertiesFileName); // Begin transaction logger.info("> Starting a read/write transaction ..."); tx = helloGraphDB.beginTransaction(AccessMode.READ_WRITE); //create head vertex HeaderVertex head = new HeaderVertex("JSON File"); helloGraphDB.addVertex(head); try { String sCurrentLine; br = new BufferedReader(new FileReader("C:/Users/ji/Desktop/example.json")); while ((sCurrentLine = br.readLine()) != null) { Object obj; try { obj = parser.parse(sCurrentLine); JSONObject jsonObject = (JSONObject) obj; //code to create vertex logger.info("> Creating Start vertices ..."); String start = (String) jsonObject.get("start"); StartVertex startV = new StartVertex(start); helloGraphDB.addVertex(startV); String end = (String) jsonObject.get("end"); //System.out.println(end); EndVertex endV = new EndVertex(end); helloGraphDB.addVertex(endV); String rel = (String) jsonObject.get("rel"); //System.out.println(rel); logger.info("> Creating Relationship edge ..."); Relationship relationship1 = new Relationship(""); Relationship relationship2 = new Relationship(rel); // Connect edges logger.info("> Connecting vertices ..."); startV.addEdge(relationship1, head, EdgeKind.BIDIRECTIONAL, (short) 0); endV.addEdge(relationship2, startV, EdgeKind.BIDIRECTIONAL, (short) 0); } catch (ParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } catch (IOException e) { e.printStackTrace(); } finally { try { if (br != null)br.close(); } catch (IOException ex) { ex.printStackTrace(); } } // Specify a named root for traversal logger.info("> Naming a root vertex ..."); helloGraphDB.nameVertex("JSON File", head); // Commit to save your changes to the graph database logger.info("> Committing changes ..."); tx.commit(); } catch (ConfigurationException cE) { logger.warn("> Configuration Exception was thrown ... "); logger.error(cE.getMessage()); } finally { // If the transaction was not committed, complete // will roll it back if (tx != null) tx.complete(); if (helloGraphDB != null) { helloGraphDB.close(); logger.info("> On Exit: Closed graph database"); } } } } // HINT: Add class definitions for Person and Meeting classes here. class HeaderVertex extends BaseVertex { private String header; public HeaderVertex (String header) { setStartName(header); } public void setStartName (String header) { markModified(); this.header = header; } public String toString() { fetch(); return this.header; } } class StartVertex extends BaseVertex { private String start; public StartVertex (String start) { setStartName(start); } public void setStartName (String start) { markModified(); this.start = start; } public String toString() { fetch(); return this.start; } } class EndVertex extends BaseVertex { private String end; public EndVertex (String end) { setEndVertex(end); } public void setEndVertex (String end) { markModified(); this.end = end; } public String toString() { fetch(); return this.end; } } class Relationship extends BaseEdge { private String rel; public Relationship (String rel) { setRelationship(rel); } public void setRelationship (String rel) { markModified(); this.rel = rel; } public String toString() { fetch(); return this.rel; } } </code></pre> <p>All helps are appreciated! Please help me this coding noob! :( Thank you!</p>

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