JAVA-5967 : Update Introduction to Spring Data Solr

persistence-modules/spring-data-solr/src/main/java/com/baeldung/spring/data/solr/config/SolrConfig.java

@@ -9,13 +9,13 @@ import org.springframework.data.solr.core.SolrTemplate;
 import org.springframework.data.solr.repository.config.EnableSolrRepositories;
 
 @Configuration
-@EnableSolrRepositories(basePackages = "com.baeldung.spring.data.solr.repository", namedQueriesLocation = "classpath:solr-named-queries.properties", multicoreSupport = true)
+@EnableSolrRepositories(basePackages = "com.baeldung.spring.data.solr.repository", namedQueriesLocation = "classpath:solr-named-queries.properties")
 @ComponentScan
 public class SolrConfig {
 
     @Bean
     public SolrClient solrClient() {
-        return new HttpSolrClient("http://localhost:8983/solr");
+        return new HttpSolrClient.Builder("http://localhost:8983/solr").build();
     }
 
     @Bean

persistence-modules/spring-data-solr/src/main/java/com/baeldung/spring/data/solr/repository/ProductRepository.java

@@ -1,6 +1,7 @@
 package com.baeldung.spring.data.solr.repository;
 
 import java.util.List;
+import java.util.Optional;
 
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
@@ -11,6 +12,8 @@ import com.baeldung.spring.data.solr.model.Product;
 
 public interface ProductRepository extends SolrCrudRepository<Product, String> {
 
+    public Optional<Product> findById(String id);
+    
     public List<Product> findByName(String name);
 
     @Query("id:*?0* OR name:*?0*")