version 1.1.0: -removes creation of ArrayList in constructor, works w…

…ith collections -adds groupBy method
loukaspd · Jul 22, 2019 · 951081d · 951081d
1 parent bd5c861
commit 951081d
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Showing 6 changed files with 354 additions and 30 deletions.
diff --git a/LinqArraylist/build.gradle b/LinqArraylist/build.gradle
@@ -9,8 +9,8 @@ ext {
     libraryName = 'LinqArraylist'
     artifact = 'LinqArraylist'
 
-    libraryDescription = 'Linq-like functionality for Java ArrayList'
-    libraryVersion = '1.0.0'
+    libraryDescription = 'Linq-like functionality for Java Collections'
+    libraryVersion = '1.1.0'
 
     siteUrl = 'https://github.com/loukaspd/LinqArraylist'
     gitUrl = 'https://github.com/loukaspd/LinqArraylist.git'

diff --git a/LinqArraylist/src/main/java/loukaspd/gr/linqarraylistproject/LinqArrayList.java b/LinqArraylist/src/main/java/loukaspd/gr/linqarraylistproject/LinqArrayList.java
@@ -1,87 +1,126 @@
 package loukaspd.gr.linqarraylistproject;
 
-import java.util.ArrayList;
-import java.util.Collection;
+import java.util.*;
 
 public class LinqArrayList<E> {
     // ---------- Class variables - Constructor ---------- //
-    private final ArrayList<E> _arrayList;
+    private final Collection<E> _collection;
     public ArrayList<E> getArrayList() {
-        return _arrayList;
+        if (_collection instanceof ArrayList) return (ArrayList<E>) _collection;
+        return new ArrayList<>(_collection);
     }
+    public Collection<E> getCollection() {return _collection;}
 
-    public LinqArrayList(ArrayList<E> arrayList){
-        _arrayList = arrayList;
-    }
     public LinqArrayList(Collection<E> collection) {
-        _arrayList = new ArrayList<E>(collection);
+        _collection = collection;
     }
 
 
     // ---------- Interfaces ---------- //
     public interface VoidFunc<E> {
         void lambda(E item);
-    };
+    }
     public interface BooleanFunc<E> {
         boolean lambda(E item);
-    };
+    }
     public interface SelectFunc<E,T> {
         T lambda(E item);
-    };
+    }
+    public interface SelectManyFunc<E,T> {
+        Collection<T> lambda(E item);
+    }
     public interface SumFunc<E> {
         double lambda(E item);
-    };
+    }
 
 
 
     // ---------- Methods ---------- //
     public void forEach(VoidFunc<E> func) {
-        for(E item : _arrayList) {
+        Enumeration<E> enumeration = Collections.enumeration(_collection);
+
+        while(enumeration.hasMoreElements()) {
+            E item = enumeration.nextElement();
+
             func.lambda(item);
         }
     }
 
     public E first(BooleanFunc<E> func){
-        for(E item : _arrayList) {
+        Enumeration<E> enumeration = Collections.enumeration(_collection);
+        while(enumeration.hasMoreElements()) {
+            E item = enumeration.nextElement();
+
             if (func.lambda(item)) return item;
         }
         throw new IllegalStateException();
     }
 
     public E firstOrDefault(BooleanFunc<E> func){
-        for(E item : _arrayList) {
+        Enumeration<E> enumeration = Collections.enumeration(_collection);
+        while(enumeration.hasMoreElements()) {
+            E item = enumeration.nextElement();
+
             if (func.lambda(item)) return item;
         }
         return null;
     }
 
     public LinqArrayList<E> where(BooleanFunc<E> func) {
         ArrayList<E> result = new ArrayList<E>();
-        for(E item : _arrayList) {
+        Enumeration<E> enumeration = Collections.enumeration(_collection);
+        while(enumeration.hasMoreElements()) {
+            E item = enumeration.nextElement();
+
             if (func.lambda(item)) result.add(item);
         }
         return new LinqArrayList<E>(result);
     }
 
     public <T> LinqArrayList<T> select(SelectFunc<E,T> func) {
         ArrayList<T> result = new ArrayList<T>();
-        for(E item : _arrayList) {
+
+        Enumeration<E> enumeration = Collections.enumeration(_collection);
+        while(enumeration.hasMoreElements()) {
+            E item = enumeration.nextElement();
+
             result.add(func.lambda(item));
         }
         return new LinqArrayList<T>(result);
     }
 
+    public <T> LinqArrayList<T> selectMany(SelectManyFunc<E,T> func) {
+        ArrayList<T> result = new ArrayList<T>();
+
+        Enumeration<E> enumeration = Collections.enumeration(_collection);
+        while(enumeration.hasMoreElements()) {
+            E item = enumeration.nextElement();
+
+            Collection<T> collection = func.lambda(item);
+            if (collection == null) continue;
+            result.addAll(collection);
+        }
+
+        return new LinqArrayList<T>(result);
+    }
+
     public boolean any(BooleanFunc<E> func) {
-        for(E item : _arrayList) {
+        Enumeration<E> enumeration = Collections.enumeration(_collection);
+        while(enumeration.hasMoreElements()) {
+            E item = enumeration.nextElement();
+
             if (func.lambda(item)) return true;
         }
         return false;
     }
 
     public boolean remove(BooleanFunc<E> func) {
-        for(E item : _arrayList) {
+        Enumeration<E> enumeration = Collections.enumeration(_collection);
+        while(enumeration.hasMoreElements()) {
+            E item = enumeration.nextElement();
+
             if (func.lambda(item)) {
-                _arrayList.remove(item);
+                _collection.remove(item);
                 return true;
             }
         }
@@ -90,7 +129,11 @@ public boolean remove(BooleanFunc<E> func) {
 
     public LinqArrayList<E> distinct() {
         ArrayList<E> result = new ArrayList<>();
-        for(E item : _arrayList) {
+
+        Enumeration<E> enumeration = Collections.enumeration(_collection);
+        while(enumeration.hasMoreElements()) {
+            E item = enumeration.nextElement();
+
             if(!result.contains(item)) {
                 result.add(item);
             }
@@ -100,9 +143,32 @@ public LinqArrayList<E> distinct() {
 
     public double sum(SumFunc<E> func) {
         double result = 0;
-        for(E item : _arrayList) {
+
+        Enumeration<E> enumeration = Collections.enumeration(_collection);
+        while(enumeration.hasMoreElements()) {
+            E item = enumeration.nextElement();
+
             result += func.lambda(item);
         }
         return result;
     }
+
+    public <T> Hashtable<T,ArrayList<E>> groupBy(SelectFunc<E,T> func) {
+        Hashtable<T,ArrayList<E>> dictionary = new Hashtable<T,ArrayList<E>>();
+
+        Enumeration<E> enumeration = Collections.enumeration(_collection);
+        while(enumeration.hasMoreElements()) {
+            E item = enumeration.nextElement();
+
+            T key = func.lambda(item);
+            if (dictionary.containsKey(key)) dictionary.get(key).add(item);
+            else {
+                ArrayList<E> group = new ArrayList<>();
+                group.add(item);
+                dictionary.put(key, group);
+            }
+        }
+
+        return dictionary;
+    }
 }
diff --git a/Readme.md b/Readme.md
@@ -1,17 +1,20 @@
 # LinqArraylist
 
-use Linq-like functions to Java ArrayLists
+[ ![Download](https://api.bintray.com/packages/loukaspd/LinqArraylist/LinqArraylist/images/download.svg) ](https://bintray.com/loukaspd/LinqArraylist/LinqArraylist/_latestVersion)
+[![Android Arsenal]( https://img.shields.io/badge/Android%20Arsenal-LinqArraylist-green.svg?style=flat )]( https://android-arsenal.com/details/1/7060 )  
+use Linq-like functions to Java Collections
 
 
 ```
-    implementation 'gr.loukaspd:LinqArraylist:1.0.0'
+    implementation 'gr.loukaspd:LinqArraylist:{latest version}'
 ```
+where `{latest version}` corresponds to published version in [ ![Download](https://api.bintray.com/packages/loukaspd/LinqArraylist/LinqArraylist/images/download.svg) ](https://bintray.com/loukaspd/LinqArraylist/LinqArraylist/_latestVersion)
 [![Android Arsenal]( https://img.shields.io/badge/Android%20Arsenal-LinqArraylist-green.svg?style=flat )]( https://android-arsenal.com/details/1/7060 )
 
 ## Usage
-1. Instantiate a LinqArrayList object by passing it your original ArrayList
+1. Instantiate a LinqArrayList object by passing it your original Collection
 2. Apply linq methods (even chaining) like select, where etc..
-3. Get the resulting ArrayList by calling `getArrayList()` method
+3. Get the resulting Collection by calling `getCollection` or `getArrayList()` to get a new ArrayList from the collection
 
 
 ## Examples

diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,5 @@
-#Sat Jul 21 00:42:45 EEST 2018
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.1.1-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.9-rc-1-all.zip