Compile course

Author: andy1li

compiled_starters/kotlin/src/main/kotlin/Main.kt

@@ -20,7 +20,7 @@ fun main(args: Array<String>) {
         // databaseFile.skip(16) // Skip the first 16 bytes of the header
         // val pageSizeBytes = ByteArray(2) // The following 2 bytes are the page size
         // databaseFile.read(pageSizeBytes)
-        // val pageSize = java.nio.ByteBuffer.wrap(pageSizeBytes).short.toInt()
+        // val pageSize = pageSizeBytes[0].toUByte() * 256u + pageSizeBytes[1].toUByte()
         // println("database page size: $pageSize")
 
         databaseFile.close()

solutions/kotlin/01-dr6/code/src/main/kotlin/Main.kt

@@ -15,7 +15,7 @@ fun main(args: Array<String>) {
         databaseFile.skip(16) // Skip the first 16 bytes of the header
         val pageSizeBytes = ByteArray(2) // The following 2 bytes are the page size
         databaseFile.read(pageSizeBytes)
-        val pageSize = java.nio.ByteBuffer.wrap(pageSizeBytes).short.toInt()
+        val pageSize = pageSizeBytes[0].toUByte() * 256u + pageSizeBytes[1].toUByte()
         println("database page size: $pageSize")
 
         databaseFile.close()

solutions/kotlin/01-dr6/diff/src/main/kotlin/Main.kt.diff

@@ -21,12 +21,12 @@
 -        // databaseFile.skip(16) // Skip the first 16 bytes of the header
 -        // val pageSizeBytes = ByteArray(2) // The following 2 bytes are the page size
 -        // databaseFile.read(pageSizeBytes)
--        // val pageSize = java.nio.ByteBuffer.wrap(pageSizeBytes).short.toInt()
+-        // val pageSize = pageSizeBytes[0].toUByte() * 256u + pageSizeBytes[1].toUByte()
 -        // println("database page size: $pageSize")
 +        databaseFile.skip(16) // Skip the first 16 bytes of the header
 +        val pageSizeBytes = ByteArray(2) // The following 2 bytes are the page size
 +        databaseFile.read(pageSizeBytes)
-+        val pageSize = java.nio.ByteBuffer.wrap(pageSizeBytes).short.toInt()
++        val pageSize = pageSizeBytes[0].toUByte() * 256u + pageSizeBytes[1].toUByte()
 +        println("database page size: $pageSize")
 
          databaseFile.close()

solutions/kotlin/01-dr6/explanation.md

@@ -8,7 +8,7 @@ Study and uncomment the relevant code:
 databaseFile.skip(16) // Skip the first 16 bytes of the header
 val pageSizeBytes = ByteArray(2) // The following 2 bytes are the page size
 databaseFile.read(pageSizeBytes)
-val pageSize = java.nio.ByteBuffer.wrap(pageSizeBytes).short.toInt()
+val pageSize = pageSizeBytes[0].toUByte() * 256u + pageSizeBytes[1].toUByte()
 println("database page size: $pageSize")
 ```