Refactored IterableAsList to remove unnecessary call to size() and re…

…move not working cache no more calls to size() if not needed. Modifications in the underlying Iterable would lead to inconsistent cache. Removed cache completely. Caches do not work for modifyable Iterables.
yegor256 · Jun 10, 2017 · b99858d · b99858d
1 parent ebee859
commit b99858d
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Showing 2 changed files with 17 additions and 33 deletions.
diff --git a/README.md b/README.md
@@ -252,6 +252,7 @@ Note: [Checkstyle](https://en.wikipedia.org/wiki/Checkstyle) is used as a static
   - [Andriy Kryvtsun](https://github.com/englishman)
   - [Vseslav Sekorin](https://github.com/VsSekorin)
   - [Andrey Valyaev](https://github.com/DronMDF)
+  - [Tim Hinkes](https://github.com/timmeey) [Blog](https://blog.timmeey.de)
 
 ## License (MIT)
 

diff --git a/src/main/java/org/cactoos/list/IterableAsList.java b/src/main/java/org/cactoos/list/IterableAsList.java
@@ -24,7 +24,6 @@
 package org.cactoos.list;
 
 import java.util.AbstractList;
-import java.util.ArrayList;
 import java.util.List;
 import org.cactoos.func.StickyScalar;
 import org.cactoos.func.UncheckedScalar;
@@ -48,11 +47,6 @@ public final class IterableAsList<T> extends AbstractList<T> {
      */
     private final Iterable<T> source;
 
-    /**
-     * Cache for source.
-     */
-    private final List<T> cache;
-
     /**
      * Iterable length.
      */
@@ -66,7 +60,6 @@ public final class IterableAsList<T> extends AbstractList<T> {
     public IterableAsList(final Iterable<T> iterable) {
         super();
         this.source = iterable;
-        this.cache = new ArrayList<>(0);
         this.length = new UncheckedScalar<>(
             new StickyScalar<>(
                 new LengthOfIterable(iterable)
@@ -76,38 +69,28 @@ public IterableAsList(final Iterable<T> iterable) {
 
     @Override
     public T get(final int index) {
-        if (index < 0 || index >= this.size()) {
-            throw new IndexOutOfBoundsException(
-                new UncheckedText(
-                    new FormattedText(
-                        "index=%d, bounds=[%d; %d]",
-                        index,
-                        0,
-                        this.size()
-                    )
-                ).asString()
-            );
+        int position = 0;
+        for (final T elem : this.source) {
+            if (position == index) {
+                return elem;
+            }
+            position += 1;
         }
-        return this.cachedItem(index);
+        throw new IndexOutOfBoundsException(
+            new UncheckedText(
+                new FormattedText(
+                    "index=%d, bounds=[%d; %d]",
+                    index,
+                    0,
+                    this.size()
+                )
+            ).asString()
+        );
     }
 
     @Override
     public int size() {
         return this.length.asValue();
     }
 
-    /**
-     * Find item in cache by index.
-     *
-     * @param index Item index
-     * @return Cached item
-     */
-    private T cachedItem(final int index) {
-        if (this.cache.size() != this.size()) {
-            for (final T item : this.source) {
-                this.cache.add(item);
-            }
-        }
-        return this.cache.get(index);
-    }
 }