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version 1.1.0: -removes creation of ArrayList in constructor, works with collections -adds groupBy method
1 parent bd5c861 commit 951081d

6 files changed

Lines changed: 354 additions & 30 deletions

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‎LinqArraylist/build.gradle‎

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -9,8 +9,8 @@ ext {
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libraryName = 'LinqArraylist'
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artifact = 'LinqArraylist'
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libraryDescription = 'Linq-like functionality for Java ArrayList'
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libraryVersion = '1.0.0'
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libraryDescription = 'Linq-like functionality for Java Collections'
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libraryVersion = '1.1.0'
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siteUrl = 'https://github.com/loukaspd/LinqArraylist'
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gitUrl = 'https://github.com/loukaspd/LinqArraylist.git'

‎LinqArraylist/src/main/java/loukaspd/gr/linqarraylistproject/LinqArrayList.java‎

Lines changed: 88 additions & 22 deletions
Original file line numberDiff line numberDiff line change
@@ -1,87 +1,126 @@
11
package loukaspd.gr.linqarraylistproject;
22

3-
import java.util.ArrayList;
4-
import java.util.Collection;
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import java.util.*;
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public class LinqArrayList<E> {
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// ---------- Class variables - Constructor ---------- //
8-
private final ArrayList<E> _arrayList;
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private final Collection<E> _collection;
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public ArrayList<E> getArrayList() {
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return _arrayList;
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if (_collection instanceof ArrayList) return (ArrayList<E>) _collection;
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return new ArrayList<>(_collection);
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}
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public Collection<E> getCollection() {return _collection;}
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public LinqArrayList(ArrayList<E> arrayList){
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_arrayList = arrayList;
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}
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public LinqArrayList(Collection<E> collection) {
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_arrayList = new ArrayList<E>(collection);
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_collection = collection;
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}
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// ---------- Interfaces ---------- //
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public interface VoidFunc<E> {
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void lambda(E item);
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};
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}
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public interface BooleanFunc<E> {
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boolean lambda(E item);
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};
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}
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public interface SelectFunc<E,T> {
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T lambda(E item);
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};
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}
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public interface SelectManyFunc<E,T> {
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Collection<T> lambda(E item);
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}
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public interface SumFunc<E> {
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double lambda(E item);
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};
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}
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// ---------- Methods ---------- //
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public void forEach(VoidFunc<E> func) {
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for(E item : _arrayList) {
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Enumeration<E> enumeration = Collections.enumeration(_collection);
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while(enumeration.hasMoreElements()) {
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E item = enumeration.nextElement();
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func.lambda(item);
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}
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}
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public E first(BooleanFunc<E> func){
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for(E item : _arrayList) {
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Enumeration<E> enumeration = Collections.enumeration(_collection);
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while(enumeration.hasMoreElements()) {
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E item = enumeration.nextElement();
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if (func.lambda(item)) return item;
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}
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throw new IllegalStateException();
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}
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public E firstOrDefault(BooleanFunc<E> func){
52-
for(E item : _arrayList) {
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Enumeration<E> enumeration = Collections.enumeration(_collection);
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while(enumeration.hasMoreElements()) {
62+
E item = enumeration.nextElement();
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if (func.lambda(item)) return item;
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}
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return null;
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}
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public LinqArrayList<E> where(BooleanFunc<E> func) {
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ArrayList<E> result = new ArrayList<E>();
60-
for(E item : _arrayList) {
71+
Enumeration<E> enumeration = Collections.enumeration(_collection);
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while(enumeration.hasMoreElements()) {
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E item = enumeration.nextElement();
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6175
if (func.lambda(item)) result.add(item);
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}
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return new LinqArrayList<E>(result);
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}
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public <T> LinqArrayList<T> select(SelectFunc<E,T> func) {
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ArrayList<T> result = new ArrayList<T>();
68-
for(E item : _arrayList) {
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83+
Enumeration<E> enumeration = Collections.enumeration(_collection);
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while(enumeration.hasMoreElements()) {
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E item = enumeration.nextElement();
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result.add(func.lambda(item));
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}
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return new LinqArrayList<T>(result);
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}
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public <T> LinqArrayList<T> selectMany(SelectManyFunc<E,T> func) {
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ArrayList<T> result = new ArrayList<T>();
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95+
Enumeration<E> enumeration = Collections.enumeration(_collection);
96+
while(enumeration.hasMoreElements()) {
97+
E item = enumeration.nextElement();
98+
99+
Collection<T> collection = func.lambda(item);
100+
if (collection == null) continue;
101+
result.addAll(collection);
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}
103+
104+
return new LinqArrayList<T>(result);
105+
}
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public boolean any(BooleanFunc<E> func) {
75-
for(E item : _arrayList) {
108+
Enumeration<E> enumeration = Collections.enumeration(_collection);
109+
while(enumeration.hasMoreElements()) {
110+
E item = enumeration.nextElement();
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76112
if (func.lambda(item)) return true;
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}
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return false;
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}
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public boolean remove(BooleanFunc<E> func) {
82-
for(E item : _arrayList) {
118+
Enumeration<E> enumeration = Collections.enumeration(_collection);
119+
while(enumeration.hasMoreElements()) {
120+
E item = enumeration.nextElement();
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83122
if (func.lambda(item)) {
84-
_arrayList.remove(item);
123+
_collection.remove(item);
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return true;
86125
}
87126
}
@@ -90,7 +129,11 @@ public boolean remove(BooleanFunc<E> func) {
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91130
public LinqArrayList<E> distinct() {
92131
ArrayList<E> result = new ArrayList<>();
93-
for(E item : _arrayList) {
132+
133+
Enumeration<E> enumeration = Collections.enumeration(_collection);
134+
while(enumeration.hasMoreElements()) {
135+
E item = enumeration.nextElement();
136+
94137
if(!result.contains(item)) {
95138
result.add(item);
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}
@@ -100,9 +143,32 @@ public LinqArrayList<E> distinct() {
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101144
public double sum(SumFunc<E> func) {
102145
double result = 0;
103-
for(E item : _arrayList) {
146+
147+
Enumeration<E> enumeration = Collections.enumeration(_collection);
148+
while(enumeration.hasMoreElements()) {
149+
E item = enumeration.nextElement();
150+
104151
result += func.lambda(item);
105152
}
106153
return result;
107154
}
155+
156+
public <T> Hashtable<T,ArrayList<E>> groupBy(SelectFunc<E,T> func) {
157+
Hashtable<T,ArrayList<E>> dictionary = new Hashtable<T,ArrayList<E>>();
158+
159+
Enumeration<E> enumeration = Collections.enumeration(_collection);
160+
while(enumeration.hasMoreElements()) {
161+
E item = enumeration.nextElement();
162+
163+
T key = func.lambda(item);
164+
if (dictionary.containsKey(key)) dictionary.get(key).add(item);
165+
else {
166+
ArrayList<E> group = new ArrayList<>();
167+
group.add(item);
168+
dictionary.put(key, group);
169+
}
170+
}
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172+
return dictionary;
173+
}
108174
}

‎Readme.md‎

Lines changed: 7 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -1,17 +1,20 @@
11
# LinqArraylist
22

3-
use Linq-like functions to Java ArrayLists
3+
[ ![Download](https://api.bintray.com/packages/loukaspd/LinqArraylist/LinqArraylist/images/download.svg) ](https://bintray.com/loukaspd/LinqArraylist/LinqArraylist/_latestVersion)
4+
[![Android Arsenal]( https://img.shields.io/badge/Android%20Arsenal-LinqArraylist-green.svg?style=flat )]( https://android-arsenal.com/details/1/7060 )
5+
use Linq-like functions to Java Collections
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```
7-
implementation 'gr.loukaspd:LinqArraylist:1.0.0'
9+
implementation 'gr.loukaspd:LinqArraylist:{latest version}'
810
```
11+
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)
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[![Android Arsenal]( https://img.shields.io/badge/Android%20Arsenal-LinqArraylist-green.svg?style=flat )]( https://android-arsenal.com/details/1/7060 )
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## Usage
12-
1. Instantiate a LinqArrayList object by passing it your original ArrayList
15+
1. Instantiate a LinqArrayList object by passing it your original Collection
1316
2. Apply linq methods (even chaining) like select, where etc..
14-
3. Get the resulting ArrayList by calling `getArrayList()` method
17+
3. Get the resulting Collection by calling `getCollection` or `getArrayList()` to get a new ArrayList from the collection
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## Examples

‎gradle/wrapper/gradle-wrapper.properties‎

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@@ -1,6 +1,5 @@
1-
#Sat Jul 21 00:42:45 EEST 2018
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distributionBase=GRADLE_USER_HOME
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distributionPath=wrapper/dists
3+
distributionUrl=https\://services.gradle.org/distributions/gradle-5.1.1-bin.zip
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zipStoreBase=GRADLE_USER_HOME
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zipStorePath=wrapper/dists
6-
distributionUrl=https\://services.gradle.org/distributions/gradle-4.9-rc-1-all.zip

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