Aktualisierungen September, 2013 Kommentarverlauf ein-/ausschalten | Tastaturkürzel

  • Andreas Höhmann 14:25 am Wednesday, 25. September 2013 Permalink |  

    SuperCsvIterator 

    This week I created this iterator to read data from an csv file and return a list of beans. Maybe useful for other 🙂

    import java.io.IOException;
    import java.io.Reader;
    import java.util.Arrays;
    import java.util.Iterator;
    
    import javax.annotation.Nullable;
    
    import org.supercsv.cellprocessor.ift.CellProcessor;
    import org.supercsv.io.CsvBeanReader;
    import org.supercsv.prefs.CsvPreference;
    
    import com.google.common.base.Function;
    import com.google.common.collect.AbstractIterator;
    import com.google.common.collect.FluentIterable;
    import com.google.common.collect.ImmutableList;
    import com.google.common.io.Closeables;
    
    /**
     * @author Andreas Höhmann
     */
    public class SuperCsvIterator<T> extends AbstractIterator<T>
    {
       public static <T> ImmutableList<T> toList(final CsvBeanReader beanReader,
                                                 final Class<T> beanClass,
                                                 final CellProcessor[] cellProcessors ) throws IOException  {
    
           return new FluentIterable<T>() {
    
             @Override
             public Iterator<T> iterator() {
                return new CsvIterator<T>( beanClass, beanReader, cellProcessors );
             }
           }.toList();
       }
    
       public static <T> ImmutableList<T> toList(final Reader reader,
                                                 final Class<T> beanClass,
                                                 final CsvPreference csvPreference,
                                                 final CellProcessor[] cellProcessors ) throws IOException {
    
         final CsvBeanReader beanReader = new CsvBeanReader( reader, CsvPreference.STANDARD_PREFERENCE );
         try {
            return toList( beanReader, beanClass, cellProcessors );
         }
         finally {
           Closeables.close( beanReader, false );
         }
       }
    
       private static String[] trimHeaders( final String[] headers ) {
         return FluentIterable.from( Arrays.asList( headers ) ).transform( new Function<String, String>() {
    
             @Override
             @Nullable
             public String apply( @Nullable final String input )  {
               if ( input == null )
                 return null;
               return input.trim();
             }
           } ).toArray( String.class );
       }
    
       private final Class<T> beanClass;
       private final CsvBeanReader beanReader;
       private final CellProcessor[] cellProcessors;
       private final String[] headers;
    
       public SuperCsvIterator(final Class<T> beanClass,
                          final CsvBeanReader beanReader,
                          final CellProcessor[] cellProcessors ) throws IOException {
          this.beanClass = beanClass;
          this.beanReader = beanReader;
          this.cellProcessors = Arrays.copyOf( cellProcessors, cellProcessors.length );
          this.headers = trimHeaders( beanReader.getHeader( true ) );
       }
    
       @Override
       protected T computeNext() 	{
         try {
           final T result = beanReader.read( beanClass, headers, cellProcessors );
           if ( result == null ) {
             return endOfData();
           }
           return result;
         }
         catch ( final IOException e ) {
            throw new RuntimeException( "Can't compute next csv bean element", e );
         }
      }
    }
    

     

    public final class FooCsvBean {
    
       public static final String[] HEADER = new String[] { "Name", "Age", "Bar", };
       public static final CellProcessor[] CELLPROCESSOR = new CellProcessor[] { null, // Name
                                                                                 null, // Age
                                                                                 null, // Bar
                                                                               };
    
       private String name, age, bar;
    
       // Setter + Getter
    }
    
    final ImmutableList<FooCsvBean> foos = SuperCsvIterator.toList(new FileReader( fooCsvFile ),
                                                            FooCsvBean.class,
                                                            CsvPreference.STANDARD_PREFERENCE,
                                                            FooCsvBean.CELLPROCESSOR );
    
     
  • Andreas Höhmann 0:53 am Tuesday, 16. July 2013 Permalink |
    Tags: Neo4j,   

    Lets play with neo4j 

    Der „Leipziger Firmenlauf 2013“ ist nun auch langsam Geschichte. Doch als ich heute nochmals durch die Ergebnisse stöberte, kam ich auf die Idee die Daten doch einfach mal in eine „NoSQL“ Datenbank, in meinem Fall jetzt mal Neo4j, zu importieren.

    Also gesagt getan, das Besorgen der Daten ist ein Kinderspiel. Die Homepage liefert alle gewünschten Datensätze per JSON, im Chrome die „CURL“ kopieren, auf Kommandozeile ausführen, in eine Datei umleiten … fertig 🙂

    $ curl 'http://results.davengo.com/query' -H 'Origin: http://results.davengo.com' -H 'Accept-Encoding: gzip,deflate,sdch' -H 'Host: results.davengo.com' -H 'Accept-Language: en,de;q=0.8
    ,en-US;q=0.6' -H 'User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/28.0.1500.72 Safari/537.36' -H 'Content-Type: application/json' -H 
    'Accept: */*' -H 'Referer: http://results.davengo.com/?event=50d426afb8ed1d2318282f54' -H 'Cookie: __utma=9661994.565730006.1373516179.1373516179.1373909845.2; __utmb=9661994.2.10.1373909845; 
    __utmc=9661994; __utmz=9661994.1373909845.2.2.utmcsr=leipzig-firmenlauf.de|utmccn=(referral)|utmcmd=referral|utmcct=/ergebnisse2013.html; 
    __utma=268406157.662336661.1373516307.1373516307.1373909929.2; __utmb=268406157.1.10.1373909929; __utmc=268406157; __utmz=268406157.1373516307.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none); 
    projekktorplayercontrolbar_volume=0.5' -H 'Connection: keep-alive' --data-binary '{"key":"50d426afb8ed1d2318282f54", "offset":0, "limit":100000, "where":{"categoryName":"Einzelwertung"}, "order":
    {"firma":"ASC"}, "category":"Einzelwertung"}' --compressed &gt; results_2013.json
    

    Jetzt kommt der „schwierige“ Part, JSON parsen und via Spring Data Neo4j in eine Neo4j Datenbank einfügen.

    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    	<modelVersion>4.0.0</modelVersion>
    	<groupId>com.mymita.tools</groupId>
    	<artifactId>firmenlauf2013</artifactId>
    	<version>0.0.1-SNAPSHOT</version>
    	<dependencies>
    		<dependency>
    			<groupId>org.codehaus.jackson</groupId>
    			<artifactId>jackson-mapper-asl</artifactId>
    			<version>1.9.12</version>
    		</dependency>
    		<dependency>
    			<groupId>org.springframework.data</groupId>
    			<artifactId>spring-data-neo4j</artifactId>
    			<version>2.2.1.RELEASE</version>
    		</dependency>
    		<dependency>
    			<groupId>org.projectlombok</groupId>
    			<artifactId>lombok</artifactId>
    			<version>0.11.8</version>
    		</dependency>
    		<dependency>
    			<groupId>com.google.guava</groupId>
    			<artifactId>guava</artifactId>
    			<version>14.0.1</version>
    		</dependency>
    		<dependency>
    			<groupId>cglib</groupId>
    			<artifactId>cglib</artifactId>
    			<version>2.2.2</version>
    		</dependency>
    		<dependency>
    			<groupId>javax.validation</groupId>
    			<artifactId>validation-api</artifactId>
    			<version>1.1.0.Final</version>
    		</dependency>
    		<dependency>
    			<groupId>ch.qos.logback</groupId>
    			<artifactId>logback-classic</artifactId>
    			<version>1.0.13</version>
    		</dependency>
    	</dependencies>
    	<build>
    		<plugins>
    			<plugin>
    				<groupId>org.apache.maven.plugins</groupId>
    				<artifactId>maven-compiler-plugin</artifactId>
    				<version>3.1</version>
    				<configuration>
    					<source>1.7</source>
    					<target>1.7</target>
    				</configuration>
    			</plugin>
    		</plugins>
    	</build>
    </project>
    

    Der Importerservice

    package com.mymita.firmenlauf2013.service;
    
    import java.io.IOException;
    import java.util.Map;
    
    import lombok.AllArgsConstructor;
    import lombok.Getter;
    import lombok.Setter;
    import lombok.ToString;
    
    import org.codehaus.jackson.map.ObjectMapper;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.core.io.ClassPathResource;
    import org.springframework.data.neo4j.support.Neo4jTemplate;
    import org.springframework.stereotype.Service;
    import org.springframework.transaction.annotation.Transactional;
    
    import com.google.common.base.Objects;
    import com.google.common.collect.Maps;
    import com.mymita.firmenlauf2013.model.Company;
    import com.mymita.firmenlauf2013.model.Run;
    import com.mymita.firmenlauf2013.model.Runner;
    import com.mymita.firmenlauf2013.model.Team;
    
    @Service
    public class ImportService {
    
    	@Getter
    	@AllArgsConstructor
    	@ToString
    	public static class JsonRunner {
    
    		public JsonRunner(Object[] data) {
    			this((Integer) data[0], (Integer) data[1], (Integer) data[2],
    					(Integer) data[3], (String) data[4], (String) data[5],
    					(String) data[6], (String) data[7], (String) data[8],
    					(String) data[9], (String) data[10]);
    		}
    
    		Integer platz;
    		Integer platzMaennlich;
    		Integer platzWeiblich;
    		Integer nummer;
    		String vorname;
    		String nachname;
    		String team;
    		String zeit;
    		String firma;
    		String dummy;
    		String key;
    	}
    
    	@Getter
    	@Setter
    	public static class JsonRunners {
    		Object[][] items;
    	}
    
    	Logger logger = LoggerFactory.getLogger(getClass());
    
    	@Autowired
    	private Neo4jTemplate template;
    
    	private final Map<String, Company> companies = Maps.newHashMap();
    	private final Map<String, Team> teams = Maps.newHashMap();
    	private final Map<Integer, Runner> runners = Maps.newHashMap();
    	private final Map<String, Run> runs = Maps.newHashMap();
    
    	@Transactional
    	public void importData() {
    		try {
    			JsonRunners jsonRunners = new ObjectMapper().readValue(
    					new ClassPathResource("results.json").getInputStream(),
    					JsonRunners.class);
    			for (int i = 0; i < jsonRunners.items.length; i++) {
    				JsonRunner jsonRunner = new JsonRunner(jsonRunners.items[i]);
    				String teamName = jsonRunner.getTeam();
    				String companyName = jsonRunner.getFirma();
    				String time = jsonRunner.getZeit();
    				Company company = companies.get(companyName);
    				if (company == null) {
    					company = new Company(Objects.firstNonNull(companyName,
    							"NONAME"));
    					template.save(company);
    					companies.put(company.getName(), company);
    					logger.debug("Created company '{}'", company);
    				}
    				Team team = teams.get(teamName);
    				if (team == null) {
    					team = new Team(teamName).sponsoredBy(company);
    					template.save(team);
    					teams.put(team.getName(), team);
    					logger.debug("Created team '{}'", team);
    				}
    				Run run = runs.get(time);
    				if (run == null) {
    					run = new Run(time);
    					template.save(run);
    					runs.put(run.getTime(), run);
    					logger.debug("Created run '{}'", run);
    				}
    				Runner runner = new Runner(jsonRunner.getNummer(),
    						jsonRunner.getVorname(), jsonRunner.getNachname())
    						.fightFor(team).finished(run);
    				template.save(runner);
    				runners.put(runner.getNumber(), runner);
    				logger.debug("Created runner '{}'", runner);
    			}
    			for (Team t : teams.values()) {
    				template.save(t);
    				logger.debug("Updated team '{}'", t);
    			}
    			for (Run r : runs.values()) {
    				template.save(r);
    				logger.debug("Updated run '{}'", r);
    			}
    		} catch (IOException e) {
    			e.printStackTrace();
    		}
    	}
    }
    

    Der Spring Context

    <?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
    	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:neo4j="http://www.springframework.org/schema/data/neo4j"
    	xmlns:tx="http://www.springframework.org/schema/tx" xmlns:context="http://www.springframework.org/schema/context"
    	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
    		                http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd
    		                http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
    		                http://www.springframework.org/schema/data/neo4j http://www.springframework.org/schema/data/neo4j/spring-neo4j.xsd">
    	<neo4j:repositories base-package="com.mymita.firmenlauf2013" />
    	<neo4j:config graphDatabaseService="graphDatabaseService" />
    	<bean id="graphDatabaseService" class="org.neo4j.kernel.EmbeddedGraphDatabase"
    		destroy-method="shutdown">
    		<constructor-arg value="target/firmenlauf2013.db" />
    	</bean>
    	<context:annotation-config />
    	<context:component-scan base-package="com.mymita.firmenlauf2013" />
    	<tx:annotation-driven mode="proxy"
    		transaction-manager="transactionManager" />
    </beans>
    

    Und ein kleines Hauptprogramm um alles zu starten

    package com.mymita.firmenlauf2013.importer;
    
    import java.io.File;
    import java.io.IOException;
    
    import org.neo4j.kernel.impl.util.FileUtils;
    import org.springframework.context.support.ClassPathXmlApplicationContext;
    
    import com.mymita.firmenlauf2013.service.ImportService;
    
    public class Importer {
    
    	public static void main(String[] args) throws IOException {
    		FileUtils.deleteRecursively(new File("target/firmenlauf2013.db"));
    		ClassPathXmlApplicationContext ctx = new ClassPathXmlApplicationContext(
    				"classpath:application-context.xml");
    		try {
    			new Importer().importData(ctx);
    		} finally {
    			ctx.close();
    		}
    	}
    
    	private void importData(ClassPathXmlApplicationContext ctx) {
            ctx.getBean(ImportService.class).importData();
        }
    
    }
    

    Die NodeEntites sehen folgendermassen aus …

    package com.mymita.firmenlauf2013.model;
    
    import lombok.ToString;
    import org.springframework.data.neo4j.annotation.GraphId;
    
    @ToString
    public abstract class AbstractEntity {
    
    	@GraphId
    	private Long id;
    
    	public Long getId() {
    		return id;
    	}
    
    	@Override
    	public boolean equals(Object obj) {
    		if (this == obj) {
    			return true;
    		}
    		if (id == null || obj == null || !getClass().equals(obj.getClass())) {
    			return false;
    		}
    		return id.equals(((AbstractEntity) obj).id);
    	}
    
    	@Override
    	public int hashCode() {
    		return id == null ? 0 : id.hashCode();
    	}
    }
    

    Die Firma für die ein Team von Läufern startete

    package com.mymita.firmenlauf2013.model;
    import lombok.Getter;
    import lombok.NoArgsConstructor;
    import lombok.ToString;
    
    import org.springframework.data.annotation.TypeAlias;
    import org.springframework.data.neo4j.annotation.Indexed;
    import org.springframework.data.neo4j.annotation.NodeEntity;
    
    @Getter
    @NoArgsConstructor
    @ToString(callSuper=true)
    @NodeEntity
    @TypeAlias("Company")
    public class Company extends AbstractEntity {
    
        @Indexed(unique=true)
        private String name;
    
        public Company(String name) {
    		this.name = name;
    	}
    
    }
    

    Das Team von Läufern

    package com.mymita.firmenlauf2013.model;
    import java.util.Set;
    
    import lombok.Getter;
    import lombok.NoArgsConstructor;
    import lombok.ToString;
    
    import org.springframework.data.annotation.TypeAlias;
    import org.springframework.data.neo4j.annotation.Indexed;
    import org.springframework.data.neo4j.annotation.NodeEntity;
    import org.springframework.data.neo4j.annotation.RelatedTo;
    
    import com.google.common.collect.Sets;
    
    @Getter
    @NoArgsConstructor
    @ToString(callSuper=true, exclude={"runners"})
    @NodeEntity
    @TypeAlias("Team")
    public class Team extends AbstractEntity {
    
        @Indexed(unique=true)
        private String name;
        @RelatedTo(type="have")
        private Set<Runner> runners = Sets.newHashSet();
        @RelatedTo(type="sponsored_by")
        private Company company;
    
        public Team(String name) {
    		this.name = name;
    	}
    
        public Team sponsoredBy(Company company) {
        	this.company = company;
        	return this;
        }
    
        public Team have(Runner runner) {
        	runners.add(runner);
        	return this;
        }
    
    }
    

    Ein Läufer

    package com.mymita.firmenlauf2013.model;
    import lombok.Getter;
    import lombok.NoArgsConstructor;
    import lombok.ToString;
    
    import org.springframework.data.annotation.TypeAlias;
    import org.springframework.data.neo4j.annotation.Indexed;
    import org.springframework.data.neo4j.annotation.NodeEntity;
    import org.springframework.data.neo4j.annotation.RelatedTo;
    
    @Getter
    @NoArgsConstructor
    @ToString(callSuper=true, exclude={"run", "team"})
    @NodeEntity
    @TypeAlias("Runner")
    public class Runner extends AbstractEntity{
    
        @Indexed(numeric=true,unique=true)
        private Integer number;
        @Indexed
        private String firstName;
        @Indexed
        private String lastName;
        @RelatedTo(type="fight_for")
        private Team team;
        @RelatedTo(type="finished")
        private Run run;
    
        public Runner(Integer number, String firstName, String lastName) {
    		this.number = number;
    		this.firstName = firstName;
    		this.lastName = lastName;
        }
    
        public Runner fightFor(Team team) {
        	this.team=team;
        	team.have(this);
        	return this;
        }
    
        public Runner finished(Run run) {
        	this.run=run;
        	run.finishedBy(this);
        	return this;
        }
    
    }
    

    Und das Ergebnis eines Laufs

    package com.mymita.firmenlauf2013.model;
    import java.util.Set;
    
    import lombok.Getter;
    import lombok.NoArgsConstructor;
    import lombok.ToString;
    
    import org.springframework.data.annotation.TypeAlias;
    import org.springframework.data.neo4j.annotation.NodeEntity;
    import org.springframework.data.neo4j.annotation.RelatedTo;
    
    import com.google.common.collect.Sets;
    
    @Getter
    @NoArgsConstructor
    @ToString(callSuper=true, exclude={"runners"})
    @NodeEntity
    @TypeAlias("Run")
    public class Run extends AbstractEntity{
    
    	private String time;
    
    	@RelatedTo(type="finished_by")
    	private Set<Runner> runners = Sets.newHashSet();
    
        public Run(String time) {
    		this.time = time;
        }
    
    	public Run finishedBy(Runner runner) {
    		runners.add(runner);
    		return this;
    	}
    }
    

    Ergebnis der ganze Mühen ist ein Verzeichnis im target Ordner des Mavenprojekts, dessen Inhalt in einen Neo4j-Server (http://www.neo4j.org/download) kopiert wird. Ist der Server hochgefahren, kann man unter http://localhost:7474 das Ergebnis bestaunen 🙂

    Eine kleine Abfrage bringt dann auch alle meine lieben Kollegen vom „Running suckz“ Team zum Vorschein

    neo4j_firmenlauf2013

     
  • Andreas Höhmann 12:15 am Thursday, 17. November 2011 Permalink |
    Tags: guava, hierarchical, iterator   

    Hierarchical Iterator 

    import static com.google.common.collect.ImmutableList.of;
    
    import java.util.Iterator;
    import java.util.LinkedList;
    
    import com.google.common.collect.AbstractIterator;
    import com.google.common.collect.Lists;
    
    /**
     * This Iterator could be used for hierarchical data structure (e.g. Trees).
     *
     * @author Andreas Höhmann
     * @param <T>
     */
    public abstract class AbstractHierarchialIterator<T> extends AbstractIterator<T> {
    
       private final LinkedList<Iterable<T>> stack = Lists.newLinkedList();
       private Iterator<T> current;
    
       public AbstractHierarchialIterator(final T start) {
          this(of(start));
       }
    
       private AbstractHierarchialIterator(final Iterable<T> start) {
          current = start.iterator();
       }
    
       /**
        * An concrete hierarchical iterator has to implement a method to 
        * visit the children of an element.
        *
        * @param currentElement
        * @return never <code>null</code>
        */
       protected abstract Iterable<T> childrenOf(T currentElement);
    
       @Override
       protected T computeNext() {
          while (true) {
             if (current.hasNext()) {
                final T next = current.next();
                stack.add(childrenOf(next));
                return next;
             }
             if (stack.isEmpty()) {
                break;
             }
             current = stack.removeFirst().iterator();
          }
          return endOfData();
       }
    }
    

    Examples

    AbstractHierarchialIterator<Foobar> i = 
        new AbstractHierarchialIterator<Foobar>(foobarStart) {
    
        @Override
        protected Iterable<Foobar> childrenOf(final Foobar currentElement) {
            // <--- here you have to implement something
            return currentElement.getFoobarChildren(); 
        }
    };
    
    // example 1 - show all foobars
    while (i.hasNext()) {
        System.out.println(i.next());
    }
    
    // example 2 - search the first "foo"
    Foobar foo = com.google.common.collect.Iterators.find(i, new Predicate<Foobar>() {
    
          @Override
          public boolean apply(final Foobar input) {
            return "foo".equals(input.getName());
          }
        }, null);
    

    🙂

     
    • bkiew 17:11 am Samstag, 19. November 2011 Permalink | Zum Antworten anmelden

      Some questions.
      a) The variable „stack“ is a LinkedList, why not a real „Stack“?
      b) In which order will the children be processed? In-, pre- or post-order? It is not configurable nor documented 😛

      Greetings, Ben

    • Andreas Höhmann 1:24 am Dienstag, 22. November 2011 Permalink | Zum Antworten anmelden

      Hi Ben,

      a) what class do you mean? Vector?
      b) this iterator will do it with http://en.wikipedia.org/wiki/Breadth-first_search, this simple code doesn’t need any documentation 😉 … you are right … a next step could be the usage of the strategy pattern, in combination with the builder pattern it would be quite easy to support all aspects of traversing a hierarchical data-structure.

      cya
      höhmi

      • xaerxess 20:23 am Montag, 20. August 2012 Permalink | Zum Antworten anmelden

        ad. a) ArrayDeque is superior to LinkedList (and Stack of course) if you use Java 6 and don’t need List interface goodies (positional get mainly). It even outperforms ArrayList; see this benchmark.

c
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