From 64e7016821f147aa83d5f7835fbb6b8b6bd32072 Mon Sep 17 00:00:00 2001
From: Stuart McCulloch <mcculls@gmail.com>
Date: Sun, 23 Jan 2022 21:19:39 +0000
Subject: [PATCH 1/2] Cache and re-use binding lookups in
 PlaceholderBeanProvider

---
 .../org/eclipse/sisu/wire/BeanProviders.java  |  2 +-
 .../sisu/wire/PlaceholderBeanProvider.java    | 20 ++++++++++++++-----
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/org.eclipse.sisu.inject/src/org/eclipse/sisu/wire/BeanProviders.java b/org.eclipse.sisu.inject/src/org/eclipse/sisu/wire/BeanProviders.java
index f7402aba..718238db 100644
--- a/org.eclipse.sisu.inject/src/org/eclipse/sisu/wire/BeanProviders.java
+++ b/org.eclipse.sisu.inject/src/org/eclipse/sisu/wire/BeanProviders.java
@@ -167,7 +167,7 @@ public V get()
      */
     public <V> Provider<V> placeholderOf( final Key<V> key )
     {
-        return new PlaceholderBeanProvider<V>( locator, key );
+        return new PlaceholderBeanProvider<V>( this, key );
     }
 
     /**
diff --git a/org.eclipse.sisu.inject/src/org/eclipse/sisu/wire/PlaceholderBeanProvider.java b/org.eclipse.sisu.inject/src/org/eclipse/sisu/wire/PlaceholderBeanProvider.java
index f73e8871..6ec2e9dd 100644
--- a/org.eclipse.sisu.inject/src/org/eclipse/sisu/wire/PlaceholderBeanProvider.java
+++ b/org.eclipse.sisu.inject/src/org/eclipse/sisu/wire/PlaceholderBeanProvider.java
@@ -10,12 +10,13 @@
  *******************************************************************************/
 package org.eclipse.sisu.wire;
 
+import java.util.AbstractMap.SimpleImmutableEntry;
 import java.util.Map;
+import java.util.Map.Entry;
 
 import javax.inject.Inject;
 
 import org.eclipse.sisu.Parameters;
-import org.eclipse.sisu.inject.BeanLocator;
 
 import com.google.inject.Key;
 import com.google.inject.Provider;
@@ -49,17 +50,19 @@ final class PlaceholderBeanProvider<V>
     @Inject
     private TypeConverterCache converterCache;
 
-    private final Provider<BeanLocator> locator;
+    private final BeanProviders beans;
 
     private final Key<V> placeholderKey;
 
+    private volatile Entry<Key<?>, Provider<?>> cachedLookup;
+
     // ----------------------------------------------------------------------
     // Constructors
     // ----------------------------------------------------------------------
 
-    PlaceholderBeanProvider( final Provider<BeanLocator> locator, final Key<V> key )
+    PlaceholderBeanProvider( final BeanProviders beans, final Key<V> key )
     {
-        this.locator = locator;
+        this.beans = beans;
         placeholderKey = key;
     }
 
@@ -117,9 +120,16 @@ public V get()
     // Implementation methods
     // ----------------------------------------------------------------------
 
+    @SuppressWarnings( { "unchecked", "rawtypes" } )
     private <T> T lookup( final Key<T> key )
     {
-        return BeanProviders.firstOf( locator.get().locate( key ) );
+        Entry<Key<?>, Provider<?>> lookup = cachedLookup;
+        if ( null == lookup || !key.equals( lookup.getKey() ) )
+        {
+            lookup = new SimpleImmutableEntry( key, beans.firstOf( key ) );
+            cachedLookup = lookup;
+        }
+        return (T) lookup.getValue().get();
     }
 
     private static String nullify( final String value )

From 3696fdbc5b0450e136d3679a0c7048375cfb996d Mon Sep 17 00:00:00 2001
From: Stuart McCulloch <mcculls@gmail.com>
Date: Sun, 23 Jan 2022 22:08:09 +0000
Subject: [PATCH 2/2] Cache and re-use binding lookups in BeanProviders.firstOf

---
 .../org/eclipse/sisu/wire/BeanProviders.java   | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/org.eclipse.sisu.inject/src/org/eclipse/sisu/wire/BeanProviders.java b/org.eclipse.sisu.inject/src/org/eclipse/sisu/wire/BeanProviders.java
index 718238db..a2b2ca52 100644
--- a/org.eclipse.sisu.inject/src/org/eclipse/sisu/wire/BeanProviders.java
+++ b/org.eclipse.sisu.inject/src/org/eclipse/sisu/wire/BeanProviders.java
@@ -155,9 +155,16 @@ <V> Provider<V> firstOf( final Key<V> key )
         final Provider<Iterable<? extends BeanEntry<Annotation, V>>> beanEntries = beanEntriesOf( key );
         return new Provider<V>()
         {
+            private volatile Iterable<? extends BeanEntry<?, V>> cachedLookup;
+
             public V get()
             {
-                return firstOf( beanEntries.get() );
+                if ( null == cachedLookup )
+                {
+                    cachedLookup = beanEntries.get();
+                }
+                final Iterator<? extends BeanEntry<?, V>> itr = cachedLookup.iterator();
+                return itr.hasNext() ? itr.next().getProvider().get() : null;
             }
         };
     }
@@ -169,13 +176,4 @@ public <V> Provider<V> placeholderOf( final Key<V> key )
     {
         return new PlaceholderBeanProvider<V>( this, key );
     }
-
-    /**
-     * Selects first bean from the sequence; or null if none is available.
-     */
-    public static <V> V firstOf( final Iterable<? extends Entry<?, V>> entries )
-    {
-        final Iterator<? extends Entry<?, V>> itr = entries.iterator();
-        return itr.hasNext() ? itr.next().getValue() : null;
-    }
 }