Solrj Example

./pom.xml
./src/main/java/com/prismoskills/solrj/pojos/Item.java
./src/main/java/com/prismoskills/solrj/SolrDao.java
./src/main/java/com/prismoskills/solrj/SolrjExample.java
./src/main/java/com/prismoskills/solrj/SolrServerFactory.java
./src/test/java/com/prismoskills/solrj/AppTest.java

1. pom.xml needs to have the following dependencies:
   

   <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.prismoskills.solrj</groupId>
     <artifactId>solrj_example</artifactId>
     <version>1.0-SNAPSHOT</version>
     <packaging>jar</packaging>
   
     <name>example</name>
     <url>http://maven.apache.org</url>
   
     <properties>
       <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
   
   
   
     <dependencies>
   
       <dependency>
         <groupId>junit</groupId>
         <artifactId>junit</artifactId>
         <version>3.8.1</version>
         <scope>test</scope>
       </dependency>
   
       <dependency>
         <artifactId>solr-solrj</artifactId>
         <groupId>org.apache.solr</groupId>
         <version>4.1.0</version>
         <type>jar</type>
         <scope>compile</scope>
       </dependency>
   
       <dependency>
         <groupId>org.slf4j</groupId>
         <artifactId>slf4j-simple</artifactId>
         <version>1.7.2</version>
       </dependency>
   
   	<dependency>
   	  <groupId>commons-logging</groupId>
   	  <artifactId>commons-logging</artifactId>
   	  <version>1.1.1</version>
       </dependency>
   
     </dependencies>
   
   
     <build>
       <plugins>
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-shade-plugin</artifactId>
           <version>2.1</version>
           <configuration>
             <transformers>
               <transformer implementation=
                 "org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                 <manifestEntries>
                   <Main-Class>com.prismoskills.solrj.SolrjExample</Main-Class>
                 </manifestEntries>
               </transformer>
             </transformers>
           </configuration>
           <executions>
             <execution>
               <phase>package</phase>
               <goals>
                 <goal>shade</goal>
               </goals>
             </execution>
           </executions>
         </plugin>
       </plugins>
     </build>
   
   </project>
   

   
   
   
2. Item.java is a normal POJO class.

   package com.prismoskills.solrj.pojos;
   
   import org.apache.solr.client.solrj.beans.Field;
   
   public class Item 
   {
       @Field("id")
       String id;
       @Field("name")
       String name;
       @Field
       Float price;
       
       public Item() {} // Empty constructor is required
       
       public Item(String id, String name, Float price)
       {
           super();
           this.id = id;
           this.name = name;
           this.price = price;
       }
       
       // Getter Setters
       public String getId() {
           return id;
       }
       public void setId(String id) {
           this.id = id;
       }
       public String getName() {
           return name;
       }
       public void setName(String name) {
           this.name = name;
       }
       public Float getPrice() {
           return price;
       }
       public void setPrice(Float price) {
           this.price = price;
       }
   }
   

   
   
   
3. SolrServerFactory.java encapsulates the creation of SolrServer.

   
   package com.prismoskills.solrj;
   
   import java.util.Map;
   import java.util.concurrent.ConcurrentHashMap;
   
   import org.apache.solr.client.solrj.SolrServer;
   import org.apache.solr.client.solrj.impl.HttpSolrServer;
   
   public final class SolrServerFactory 
   {
       Map <String, SolrServer> urlToServer = new ConcurrentHashMap <String, SolrServer> ();
       static SolrServerFactory instance = new SolrServerFactory ();
       
       public static SolrServerFactory getInstance()
       {
           return instance;
       }
       
       private SolrServerFactory ()
       {
       }
       
       public SolrServer createServer (String solrURL)
       {
           if (urlToServer.containsKey(solrURL))
               return urlToServer.get(solrURL);
           
           /*
           HttpSolrServer is thread-safe and if you are using the following constructor,
           you *MUST* re-use the same instance for all requests.  If instances are created on
           the fly, it can cause a connection leak. The recommended practice is to keep a
           static instance of HttpSolrServer per solr server url and share it for all requests.
           See https://issues.apache.org/jira/browse/SOLR-861 for more details
         */
         SolrServer server = new HttpSolrServer( solrURL );
         urlToServer.put(solrURL, server);
         return server;
       }
   }
   

   
   
   
4. SolrDao.java is the most important class here.

   package com.prismoskills.solrj;
   
   import java.io.IOException;
   import java.util.Collection;
   import java.util.Collections;
   
   import org.apache.solr.client.solrj.SolrQuery;
   import org.apache.solr.client.solrj.SolrServerException;
   import org.apache.solr.client.solrj.impl.HttpSolrServer;
   import org.apache.solr.client.solrj.request.UpdateRequest;
   import org.apache.solr.client.solrj.response.QueryResponse;
   import org.apache.solr.client.solrj.response.UpdateResponse;
   import org.apache.solr.common.SolrDocumentList;
   import org.apache.solr.common.SolrInputDocument;
   
   import com.prismoskills.solrj.SolrServerFactory;
   
   public class SolrDao <T>
   {
   
       HttpSolrServer server = null;
       
       public SolrDao (String solrURL)
       {
           server = (HttpSolrServer) SolrServerFactory.getInstance().createServer(solrURL);
           configureSolr (server);
       }
       
       public void put (T dao)
       {
           put (createSingletonSet (dao));
       }
       
       public void put (Collection<T> dao)
       {
           try 
           {
               UpdateResponse rsp = server.addBeans (dao);
               System.out.println ("Added documents to solr. Time taken = " + rsp.getElapsedTime() + ". " + rsp.toString());
           }
           catch (SolrServerException e)
           {
               e.printStackTrace();
           }
           catch (IOException e)
           {
               e.printStackTrace();
           }
       }
       
       public void putDoc (SolrInputDocument doc)
       {
           putDoc (createSingletonSet(doc));
       }
       
       public void putDoc (Collection<SolrInputDocument> docs)
       {
           try 
           {
               long startTime = System.currentTimeMillis();
               UpdateRequest req = new UpdateRequest();
               req.setAction( UpdateRequest.ACTION.COMMIT, false, false );
               req.add (docs);
               UpdateResponse rsp = req.process( server );
               System.out.print ("Added documents to solr. Time taken = " + rsp.getElapsedTime() + ". " + rsp.toString());
               long endTime = System.currentTimeMillis();
               System.out.println (" , time-taken=" + ((double)(endTime-startTime))/1000.00 + " seconds");
           }
           catch (SolrServerException e)
           {
               e.printStackTrace();
           }
           catch (IOException e)
           {
               e.printStackTrace();
           }
       }
       
       public QueryResponse readAll () 
       {
           SolrQuery query = new SolrQuery();
           query.setQuery( "*:*" );
           //query.addSortField( "price", SolrQuery.ORDER.asc );
           QueryResponse rsp = null;
           try 
           {
               rsp = server.query( query );
           }
           catch (SolrServerException e) 
           {
               e.printStackTrace();
           }
           return rsp;
       }
       
       public SolrDocumentList readAllDocs ()
       {
           SolrQuery query = new SolrQuery();
           query.setQuery( "*:*" );
           //query.addSortField( "price", SolrQuery.ORDER.asc );
           QueryResponse rsp = null;
           try {
               rsp = server.query( query );
           } catch (SolrServerException e) 
           {
               e.printStackTrace();
               return null;
           }
           SolrDocumentList docs = rsp.getResults();
           return docs;
       }
       
       private void configureSolr(HttpSolrServer server) 
       {
           server.setMaxRetries(1); // defaults to 0.  > 1 not recommended.
           server.setConnectionTimeout(5000); // 5 seconds to establish TCP
           // The following settings are provided here for completeness.
           // They will not normally be required, and should only be used 
           // after consulting javadocs to know whether they are truly required.
           server.setSoTimeout(1000);  // socket read timeout
           server.setDefaultMaxConnectionsPerHost(100);
           server.setMaxTotalConnections(100);
           server.setFollowRedirects(false);  // defaults to false
           // allowCompression defaults to false.
           // Server side must support gzip or deflate for this to have any effect.
           server.setAllowCompression(false);
       }
       
       private <U> Collection<U> createSingletonSet(U dao) 
       {
           if (dao == null)
               return Collections.emptySet();
           return Collections.singleton(dao);
       }
   
   }
   

   
   
   
5. SolrjExample.java has the main() function and executes SolrDao functions.

   package com.prismoskills.solrj;
   
   import java.util.ArrayList;
   import java.util.Collection;
   import java.util.Iterator;
   import java.util.List;
   
   import org.apache.solr.client.solrj.response.QueryResponse;
   import org.apache.solr.common.SolrDocument;
   import org.apache.solr.common.SolrDocumentList;
   import org.apache.solr.common.SolrInputDocument;
   
   import com.prismoskills.solrj.SolrDao;
   import com.prismoskills.solrj.pojos.Item;
   
   
   public class SolrjExample 
   {
       String solrURL = "http://localhost:8983/solr";
       
       public static void main( String[] args )
       {
           new SolrjExample().execute();
       }
       
       public void execute () 
       {
           System.out.println( "Starting off " + this.getClass().toString());
           SolrDao<Item> solrDao = new SolrDao<Item> (solrURL);
           
           addDocuments (solrDao);
           readDocuments (solrDao);
           
           addItems (solrDao);
           readItems (solrDao);
       }
   
       private void readItems(SolrDao<Item> solrDao) 
       {
           QueryResponse rsp = solrDao.readAll();
           List<Item> beans = rsp.getBeans(Item.class);
           for (Item bean : beans)
           {
               System.out.println ("Read item " + bean.getId() + ", name = " + bean.getName());
           }
       }
   
       private void addItems(SolrDao<Item> solrDao) 
       {
           Collection <Item> items = new ArrayList <Item> (3);
           items.add(new Item ("1", "Item 1", 20.50F));
           items.add(new Item ("2", "Item 2", 10.10F));
           items.add(new Item ("3", "Item 3", 30.00F));
           solrDao.put (items);
       }
   
       private void readDocuments(SolrDao<Item> solrDao) 
       {
           SolrDocumentList docs = solrDao.readAllDocs ();
           Iterator<SolrDocument> iter = docs.iterator();
           int count=10;
   
           while (iter.hasNext() && count-- > 0) 
           {
             SolrDocument resultDoc = iter.next();
   
             String content = (String) resultDoc.getFieldValue("content");
             String id = (String) resultDoc.getFieldValue("id"); //id is the uniqueKey field
             System.out.println ("Read " + resultDoc + " with id = " + id + " and content = " + content);
           }
       }
   
       private void addDocuments(SolrDao<Item> solrDao) 
       {
           Collection<SolrInputDocument> docs = new ArrayList<SolrInputDocument>();
           for (int i=0; i<1000; i++)
               docs.add( getRandomSolrDoc (i) );
   
           solrDao.putDoc (docs);
       }
   
       private SolrInputDocument getRandomSolrDoc(int count) 
       {
           SolrInputDocument doc = new SolrInputDocument();
           doc.addField( "id", "id"+count, 1.0f );
           doc.addField( "name", "doc"+count, 1.0f );
           doc.addField( "price", count%10 );
           return doc;
       }
   }
   

   
   

Results

Starting off class com.prismoskills.solrj.SolrjExample

[main] INFO org.apache.solr.client.solrj.impl.HttpClientUtil - Creating new http client, config:maxConnections=128&maxConnectionsPerHost=32&followRedirects=false

Added documents to solr. Time taken = 238. {responseHeader={status=0,QTime=125}} , time-taken=0.24 seconds
Read SolrDocument{id=1, name=Item 1, price=20.5, price_c=20.5,USD, _version_=1450355752342388736} with id = 1 and content = null
Read SolrDocument{id=2, name=Item 2, price=10.1, price_c=10.1,USD, _version_=1450355752342388737} with id = 2 and content = null
Read SolrDocument{id=3, name=Item 3, price=30.0, price_c=30.0,USD, _version_=1450355752342388738} with id = 3 and content = null
Read SolrDocument{id=id0, name=doc0, price=0.0, price_c=0,USD, _version_=1450356064966934528} with id = id0 and content = null
Read SolrDocument{id=id1, name=doc1, price=1.0, price_c=1,USD, _version_=1450356064967983104} with id = id1 and content = null
Read SolrDocument{id=id2, name=doc2, price=2.0, price_c=2,USD, _version_=1450356064967983105} with id = id2 and content = null
Read SolrDocument{id=id3, name=doc3, price=3.0, price_c=3,USD, _version_=1450356064967983106} with id = id3 and content = null
Read SolrDocument{id=id4, name=doc4, price=4.0, price_c=4,USD, _version_=1450356064967983107} with id = id4 and content = null
Read SolrDocument{id=id5, name=doc5, price=5.0, price_c=5,USD, _version_=1450356064967983108} with id = id5 and content = null
Read SolrDocument{id=id6, name=doc6, price=6.0, price_c=6,USD, _version_=1450356064967983109} with id = id6 and content = null

Added documents to solr. Time taken = 4. {responseHeader={status=0,QTime=0}}
Read item 1, name = Item 1
Read item 2, name = Item 2
Read item 3, name = Item 3
Read item id0, name = doc0
Read item id1, name = doc1
Read item id2, name = doc2
Read item id3, name = doc3
Read item id4, name = doc4
Read item id5, name = doc5
Read item id6, name = doc6