Replace Provider with Supplier

community/kernel/src/main/java/org/neo4j/helpers/ConcurrentTransfer.java

@@ -28,7 +28,7 @@
  * Abstracts a meeting point between two threads, where a reference can change hands. It is essentially
  * a latch where a reference to a value can be set while a thread waits on it.
  */
-public class ConcurrentTransfer<TYPE> implements Consumer<TYPE>, Provider<TYPE>, Supplier<TYPE>
+public class ConcurrentTransfer<TYPE> implements Consumer<TYPE>, Supplier<TYPE>
 {
     private final CountDownLatch latch = new CountDownLatch( 1 );
     private TYPE value;
@@ -40,16 +40,6 @@ public void accept( TYPE value )
         latch.countDown();
     }
 
-    /**
-     * @deprecated use {@link #get()} instead
-     */
-    @Deprecated
-    @Override
-    public TYPE instance()
-    {
-        return get();
-    }
-
     @Override
     public TYPE get()
     {

tools/src/main/java/org/neo4j/tools/applytx/ApplyTransactionsCommand.java

@@ -22,11 +22,11 @@
 import java.io.File;
 import java.io.IOException;
 import java.io.PrintStream;
+import java.util.function.Supplier;
 
 import org.neo4j.graphdb.DependencyResolver;
 import org.neo4j.helpers.Args;
 import org.neo4j.helpers.ArrayUtil;
-import org.neo4j.helpers.Provider;
 import org.neo4j.helpers.progress.ProgressListener;
 import org.neo4j.io.fs.DefaultFileSystemAbstraction;
 import org.neo4j.io.pagecache.PageCache;
@@ -57,9 +57,9 @@
 public class ApplyTransactionsCommand extends ArgsCommand
 {
     private final File from;
-    private final Provider<GraphDatabaseAPI> to;
+    private final Supplier<GraphDatabaseAPI> to;
 
-    public ApplyTransactionsCommand( File from, Provider<GraphDatabaseAPI> to )
+    public ApplyTransactionsCommand( File from, Supplier<GraphDatabaseAPI> to )
     {
         this.from = from;
         this.to = to;
@@ -68,7 +68,7 @@ public ApplyTransactionsCommand( File from, Provider<GraphDatabaseAPI> to )
     @Override
     protected void run( Args args, PrintStream out ) throws Exception
     {
-        TransactionIdStore txIdStore = to.instance().getDependencyResolver().resolveDependency(
+        TransactionIdStore txIdStore = to.get().getDependencyResolver().resolveDependency(
                 TransactionIdStore.class );
         long fromTx = txIdStore.getLastCommittedTransaction().transactionId();
         long toTx;
@@ -91,7 +91,7 @@ else if ( whereTo.equals( "last" ) )
             toTx = Long.parseLong( whereTo );
         }
 
-        long lastApplied = applyTransactions( from, to.instance(), fromTx, toTx, out );
+        long lastApplied = applyTransactions( from, to.get(), fromTx, toTx, out );
         out.println( "Applied transactions up to and including " + lastApplied );
     }
 

tools/src/main/java/org/neo4j/tools/applytx/DatabaseRebuildTool.java

@@ -25,13 +25,13 @@
 import java.io.PrintStream;
 import java.util.Map;
 import java.util.concurrent.atomic.AtomicReference;
+import java.util.function.Supplier;
 
 import org.neo4j.consistency.ConsistencyCheckService;
 import org.neo4j.consistency.ConsistencyCheckService.Result;
 import org.neo4j.graphdb.factory.GraphDatabaseBuilder;
 import org.neo4j.graphdb.factory.GraphDatabaseFactory;
 import org.neo4j.helpers.Args;
-import org.neo4j.helpers.Provider;
 import org.neo4j.helpers.progress.ProgressMonitorFactory;
 import org.neo4j.io.fs.FileUtils;
 import org.neo4j.kernel.GraphDatabaseAPI;
@@ -188,22 +188,8 @@ private ConsoleInput console( final File fromPath, final GraphDatabaseBuilder db
         // should be restored. The commands has references to providers of things to accommodate for this.
         final AtomicReference<Store> store =
                 new AtomicReference<>( new Store( dbBuilder ) );
-        final Provider<StoreAccess> storeAccess = new Provider<StoreAccess>()
-        {
-            @Override
-            public StoreAccess instance()
-            {
-                return store.get().access;
-            }
-        };
-        final Provider<GraphDatabaseAPI> dbAccess = new Provider<GraphDatabaseAPI>()
-        {
-            @Override
-            public GraphDatabaseAPI instance()
-            {
-                return store.get().db;
-            }
-        };
+        final Supplier<StoreAccess> storeAccess = () -> store.get().access;
+        final Supplier<GraphDatabaseAPI> dbAccess = () -> store.get().db;
 
         ConsoleInput consoleInput = life.add( new ConsoleInput( in, out, prompt ) );
         consoleInput.add( "apply", new ApplyTransactionsCommand( fromPath, dbAccess ) );

tools/src/main/java/org/neo4j/tools/applytx/DumpRecordsCommand.java

@@ -24,8 +24,8 @@
 import io.airlift.airline.Cli.CliBuilder;
 
 import java.io.PrintStream;
+import java.util.function.Supplier;
 
-import org.neo4j.helpers.Provider;
 import org.neo4j.kernel.impl.core.Token;
 import org.neo4j.kernel.impl.store.LabelTokenStore;
 import org.neo4j.kernel.impl.store.PropertyKeyTokenStore;
@@ -54,10 +54,10 @@ private interface Action
     }
 
     private final Cli<Action> cli;
-    private final Provider<StoreAccess> store;
+    private final Supplier<StoreAccess> store;
 
     @SuppressWarnings( "unchecked" )
-    public DumpRecordsCommand( Provider<StoreAccess> store )
+    public DumpRecordsCommand( Supplier<StoreAccess> store )
     {
         this.store = store;
         CliBuilder<Action> builder = Cli.<Action>builder( NAME )
@@ -79,7 +79,7 @@ public DumpRecordsCommand( Provider<StoreAccess> store )
     @Override
     public void run( String[] args, PrintStream out ) throws Exception
     {
-        cli.parse( args ).run( store.instance(), out );
+        cli.parse( args ).run( store.get(), out );
     }
 
     @Override