JDBC batch transaction

  import 
  
 com.google.common.collect.ImmutableList 
 ; 
 import 
  
 java.math.BigDecimal 
 ; 
 import 
  
 java.sql.Connection 
 ; 
 import 
  
 java.sql.DriverManager 
 ; 
 import 
  
 java.sql.PreparedStatement 
 ; 
 import 
  
 java.sql.SQLException 
 ; 
 import 
  
 java.util.Arrays 
 ; 
 class 
 BatchDmlExample 
  
 { 
  
 static 
  
 class 
 Singer 
  
 { 
  
 final 
  
 long 
  
 singerId 
 ; 
  
 final 
  
 String 
  
 firstName 
 ; 
  
 final 
  
 String 
  
 lastName 
 ; 
  
 final 
  
 BigDecimal 
  
 revenues 
 ; 
  
 Singer 
 ( 
 long 
  
 singerId 
 , 
  
 String 
  
 firstName 
 , 
  
 String 
  
 lastName 
 , 
  
 BigDecimal 
  
 revenues 
 ) 
  
 { 
  
 this 
 . 
 singerId 
  
 = 
  
 singerId 
 ; 
  
 this 
 . 
 firstName 
  
 = 
  
 firstName 
 ; 
  
 this 
 . 
 lastName 
  
 = 
  
 lastName 
 ; 
  
 this 
 . 
 revenues 
  
 = 
  
 revenues 
 ; 
  
 } 
  
 } 
  
 static 
  
 void 
  
 batchDml 
 () 
  
 throws 
  
 SQLException 
  
 { 
  
 // TODO(developer): Replace these variables before running the sample. 
  
 String 
  
 projectId 
  
 = 
  
 "my-project" 
 ; 
  
 String 
  
 instanceId 
  
 = 
  
 "my-instance" 
 ; 
  
 String 
  
 databaseId 
  
 = 
  
 "my-database" 
 ; 
  
 batchDml 
 ( 
 projectId 
 , 
  
 instanceId 
 , 
  
 databaseId 
 ); 
  
 } 
  
 // This example shows how to execute a batch of DML statements with the JDBC driver. 
  
 static 
  
 void 
  
 batchDml 
 ( 
 String 
  
 projectId 
 , 
  
 String 
  
 instanceId 
 , 
  
 String 
  
 databaseId 
 ) 
  
 throws 
  
 SQLException 
  
 { 
  
 String 
  
 connectionUrl 
  
 = 
  
 String 
 . 
 format 
 ( 
  
 "jdbc:cloudspanner:/projects/%s/instances/%s/databases/%s" 
 , 
  
 projectId 
 , 
  
 instanceId 
 , 
  
 databaseId 
 ); 
  
 ImmutableList<Singer> 
  
 singers 
  
 = 
  
 ImmutableList 
 . 
 of 
 ( 
  
 new 
  
 Singer 
 ( 
 10 
 , 
  
 "Marc" 
 , 
  
 "Richards" 
 , 
  
 BigDecimal 
 . 
 valueOf 
 ( 
 10000 
 )), 
  
 new 
  
 Singer 
 ( 
 11 
 , 
  
 "Amirah" 
 , 
  
 "Finney" 
 , 
  
 BigDecimal 
 . 
 valueOf 
 ( 
 195944.10d 
 )), 
  
 new 
  
 Singer 
 ( 
 12 
 , 
  
 "Reece" 
 , 
  
 "Dunn" 
 , 
  
 BigDecimal 
 . 
 valueOf 
 ( 
 10449.90 
 )) 
  
 ); 
  
 try 
  
 ( 
 Connection 
  
 connection 
  
 = 
  
 DriverManager 
 . 
 getConnection 
 ( 
 connectionUrl 
 )) 
  
 { 
  
 connection 
 . 
 setAutoCommit 
 ( 
 false 
 ); 
  
 // Use prepared statements for the lowest possible latency when executing the same SQL string 
  
 // multiple times. 
  
 try 
  
 ( 
 PreparedStatement 
  
 statement 
  
 = 
  
 connection 
 . 
 prepareStatement 
 ( 
  
 "INSERT INTO Singers (SingerId, FirstName, LastName, Revenues)\n" 
  
  
 + 
  
 "VALUES (?, ?, ?, ?)" 
 )) 
  
 { 
  
 for 
  
 ( 
 Singer 
  
 singer 
  
 : 
  
 singers 
 ) 
  
 { 
  
 statement 
 . 
 setLong 
 ( 
 1 
 , 
  
 singer 
 . 
 singerId 
 ); 
  
 statement 
 . 
 setString 
 ( 
 2 
 , 
  
 singer 
 . 
 firstName 
 ); 
  
 statement 
 . 
 setString 
 ( 
 3 
 , 
  
 singer 
 . 
 lastName 
 ); 
  
 statement 
 . 
 setBigDecimal 
 ( 
 4 
 , 
  
 singer 
 . 
 revenues 
 ); 
  
 // Add the current parameter values to the batch. 
  
 statement 
 . 
 addBatch 
 (); 
  
 } 
  
 // Execute the batched statements. 
  
 int 
 [] 
  
 updateCounts 
  
 = 
  
 statement 
 . 
 executeBatch 
 (); 
  
 connection 
 . 
 commit 
 (); 
  
 System 
 . 
 out 
 . 
 printf 
 ( 
 "Batch insert counts: %s%n" 
 , 
  
 Arrays 
 . 
 toString 
 ( 
 updateCounts 
 )); 
  
 } 
  
 } 
  
 } 
 }