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Merge pull request #2 from eugenp/master

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Merge latest PRs
This commit is contained in:
AlexFlorinHriscu
2020-03-07 23:26:02 +02:00
committed by GitHub
parent 70799d694f 3cd2cf7cd1
commit b61b190f7c
2402 changed files with 42364 additions and 15116 deletions
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.gitignore
+1
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@@ -65,6 +65,7 @@ core-java-io/target_link.txt
core-java/src/main/java/com/baeldung/manifest/MANIFEST.MF
ethereum/logs/
jmeter/src/main/resources/*-JMeter.csv
ninja/devDb.mv.db
**/node_modules/
**/dist
akka-http/src/test/java/com/baeldung/akkahttp/UserServerUnitTest.java
+2 -2
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@@ -31,10 +31,10 @@ public class UserServerUnitTest extends JUnitRouteTest {
.assertStatusCode(404);
appRoute.run(HttpRequest.DELETE("/users/1"))
.assertStatusCode(200);
.assertStatusCode(405);
appRoute.run(HttpRequest.DELETE("/users/42"))
.assertStatusCode(200);
.assertStatusCode(405);
appRoute.run(HttpRequest.POST("/users")
.withEntity(HttpEntities.create(ContentTypes.APPLICATION_JSON, zaphod())))
algorithms-miscellaneous-2/README.md
+1
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@@ -13,4 +13,5 @@ This module contains articles about algorithms. Some classes of algorithms, e.g.
- [Create a Sudoku Solver in Java](https://www.baeldung.com/java-sudoku)
- [Displaying Money Amounts in Words](https://www.baeldung.com/java-money-into-words)
- [A Collaborative Filtering Recommendation System in Java](https://www.baeldung.com/java-collaborative-filtering-recommendations)
- [Implementing A* Pathfinding in Java](https://www.baeldung.com/java-a-star-pathfinding)
- More articles: [[<-- prev]](/../algorithms-miscellaneous-1) [[next -->]](/../algorithms-miscellaneous-3)
algorithms-miscellaneous-5/README.md
+8
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@@ -12,4 +12,12 @@ This module contains articles about algorithms. Some classes of algorithms, e.g.
- [How to Determine if a Binary Tree is Balanced](https://www.baeldung.com/java-balanced-binary-tree)
- [The Caesar Cipher in Java](https://www.baeldung.com/java-caesar-cipher)
- [Overview of Combinatorial Problems in Java](https://www.baeldung.com/java-combinatorial-algorithms)
- [Prim’s Algorithm](https://www.baeldung.com/java-prim-algorithm)
- [Maximum Subarray Problem](https://www.baeldung.com/java-maximum-subarray)
- [How to Merge Two Sorted Arrays](https://www.baeldung.com/java-merge-sorted-arrays)
- [Median of Stream of Integers using Heap](https://www.baeldung.com/java-stream-integers-median-using-heap)
- [Kruskal’s Algorithm for Spanning Trees](https://www.baeldung.com/java-spanning-trees-kruskal)
- [Balanced Brackets Algorithm in Java](https://www.baeldung.com/java-balanced-brackets-algorithm)
- [Efficiently Merge Sorted Java Sequences](https://www.baeldung.com/java-merge-sorted-sequences)
- [Introduction to Greedy Algorithms with Java](https://www.baeldung.com/java-greedy-algorithms)
- More articles: [[<-- prev]](/../algorithms-miscellaneous-4)
algorithms-miscellaneous-5/pom.xml
+12
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@@ -39,6 +39,16 @@
<artifactId>guava</artifactId>
<version>${guava.version}</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>${jackson.version}</version>
</dependency>
<dependency>
<groupId>org.junit.platform</groupId>
<artifactId>junit-platform-commons</artifactId>
<version>${junit.platform.version}</version>
</dependency>
<dependency>
<groupId>org.assertj</groupId>
@@ -66,6 +76,8 @@
<commons-codec.version>1.11</commons-codec.version>
<commons-math3.version>3.6.1</commons-math3.version>
<guava.version>28.1-jre</guava.version>
<jackson.version>2.10.2</jackson.version>
<junit.platform.version>1.6.0</junit.platform.version>
</properties>
</project>
algorithms-miscellaneous-5/src/main/java/com/baeldung/algorithms/balancedbinarytree/AVLTree.java
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@@ -0,0 +1,141 @@
package com.baeldung.algorithms.balancedbinarytree;
public class AVLTree {
public class Node {
int key;
int height;
Node left;
Node right;
Node(int key) {
this.key = key;
}
}
private Node root;
public Node find(int key) {
Node current = root;
while (current != null) {
if (current.key == key) {
break;
}
current = current.key < key ? current.right : current.left;
}
return current;
}
public void insert(int key) {
root = insert(root, key);
}
public void delete(int key) {
root = delete(root, key);
}
public Node getRoot() {
return root;
}
public int height() {
return root == null ? -1 : root.height;
}
private Node insert(Node node, int key) {
if (node == null) {
return new Node(key);
} else if (node.key > key) {
node.left = insert(node.left, key);
} else if (node.key < key) {
node.right = insert(node.right, key);
} else {
throw new RuntimeException("duplicate Key!");
}
return rebalance(node);
}
private Node delete(Node node, int key) {
if (node == null) {
return node;
} else if (node.key > key) {
node.left = delete(node.left, key);
} else if (node.key < key) {
node.right = delete(node.right, key);
} else {
if (node.left == null || node.right == null) {
node = (node.left == null) ? node.right : node.left;
} else {
Node mostLeftChild = mostLeftChild(node.right);
node.key = mostLeftChild.key;
node.right = delete(node.right, node.key);
}
}
if (node != null) {
node = rebalance(node);
}
return node;
}
private Node mostLeftChild(Node node) {
Node current = node;
/* loop down to find the leftmost leaf */
while (current.left != null) {
current = current.left;
}
return current;
}
private Node rebalance(Node z) {
updateHeight(z);
int balance = getBalance(z);
if (balance > 1) {
if (height(z.right.right) > height(z.right.left)) {
z = rotateLeft(z);
} else {
z.right = rotateRight(z.right);
z = rotateLeft(z);
}
} else if (balance < -1) {
if (height(z.left.left) > height(z.left.right)) {
z = rotateRight(z);
} else {
z.left = rotateLeft(z.left);
z = rotateRight(z);
}
}
return z;
}
private Node rotateRight(Node y) {
Node x = y.left;
Node z = x.right;
x.right = y;
y.left = z;
updateHeight(y);
updateHeight(x);
return x;
}
private Node rotateLeft(Node y) {
Node x = y.right;
Node z = x.left;
x.left = y;
y.right = z;
updateHeight(y);
updateHeight(x);
return x;
}
private void updateHeight(Node n) {
n.height = 1 + Math.max(height(n.left), height(n.right));
}
private int height(Node n) {
return n == null ? -1 : n.height;
}
public int getBalance(Node n) {
return (n == null) ? 0 : height(n.right) - height(n.left);
}
}
algorithms-miscellaneous-5/src/main/java/com/baeldung/algorithms/boruvka/BoruvkaMST.java
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@@ -0,0 +1,61 @@
package com.baeldung.algorithms.boruvka;
public class BoruvkaMST {
private static Tree mst = new Tree();
private static int totalWeight;
public BoruvkaMST(Graph graph) {
DisjointSet dSet = new DisjointSet(graph.getNodes());
// repeat at most log N times or until we have N-1 edges
for (int t = 1; t < graph.getNodes() && mst.getEdgeCount() < graph.getNodes() - 1; t = t + t) {
// foreach tree in forest, find closest edge
Edge[] closestEdgeArray = new Edge[graph.getNodes()];
for (Edge edge : graph.getAllEdges()) {
int first = edge.getFirst();
int second = edge.getSecond();
int firstParent = dSet.getParent(first);
int secondParent = dSet.getParent(second);
if (firstParent == secondParent) {
continue; // same tree
}
if (closestEdgeArray[firstParent] == null || edge.getWeight() < closestEdgeArray[firstParent].getWeight()) {
closestEdgeArray[firstParent] = edge;
}
if (closestEdgeArray[secondParent] == null || edge.getWeight() < closestEdgeArray[secondParent].getWeight()) {
closestEdgeArray[secondParent] = edge;
}
}
// add newly discovered edges to MST
for (int i = 0; i < graph.getNodes(); i++) {
Edge edge = closestEdgeArray[i];
if (edge != null) {
int first = edge.getFirst();
int second = edge.getSecond();
// don't add the same edge twice
if (dSet.getParent(first) != dSet.getParent(second)) {
mst.addEdge(edge);
totalWeight += edge.getWeight();
dSet.union(first, second);
}
}
}
}
}
public Iterable<Edge> getMST() {
return mst;
}
public int getTotalWeight() {
return totalWeight;
}
public String toString() {
return "MST: " + mst.toString() + " | Total Weight: " + totalWeight;
}
}
algorithms-miscellaneous-5/src/main/java/com/baeldung/algorithms/boruvka/DisjointSet.java
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@@ -0,0 +1,49 @@
package com.baeldung.algorithms.boruvka;
import java.util.Arrays;
public class DisjointSet {
private int[] nodeParents;
private int[] nodeRanks;
public DisjointSet(int n) {
nodeParents = new int[n];
nodeRanks = new int[n];
for (int i = 0; i < n; i++) {
nodeParents[i] = i;
nodeRanks[i] = 0;
}
}
public int getParent(int node) {
while (node != nodeParents[node]) {
node = nodeParents[node];
}
return node;
}
public void union(int node1, int node2) {
int node1Parent = getParent(node1);
int node2Parent = getParent(node2);
if (node1Parent == node2Parent) {
return;
}
if (nodeRanks[node1Parent] < nodeRanks[node2Parent]) {
nodeParents[node1Parent] = node2Parent;
}
else if (nodeRanks[node1Parent] > nodeRanks[node2Parent]) {
nodeParents[node2Parent] = node1Parent;
}
else {
nodeParents[node2Parent] = node1Parent;
nodeRanks[node1Parent]++;
}
}
public String toString() {
return "Parent: " + Arrays.toString(nodeParents) + "Rank: " + Arrays.toString(nodeRanks);
}
}
algorithms-miscellaneous-5/src/main/java/com/baeldung/algorithms/boruvka/Edge.java
+40
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@@ -0,0 +1,40 @@
package com.baeldung.algorithms.boruvka;
public class Edge {
private final int first;
private final int second;
private final int weight;
public Edge(int first, int second, int weight) {
this.first = first;
this.second = second;
this.weight = weight;
}
public double getWeight() {
return weight;
}
public int getFirst() {
return first;
}
public int getSecond() {
return second;
}
public int getOtherNode(int firstNode) {
int secondNode = 0;
if (firstNode == first)
secondNode = second;
else if (firstNode == second)
secondNode = first;
return secondNode;
}
public String toString() {
return String.format("%d-%d %d", first, second, weight);
}
}
algorithms-miscellaneous-5/src/main/java/com/baeldung/algorithms/boruvka/Graph.java
+64
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@@ -0,0 +1,64 @@
package com.baeldung.algorithms.boruvka;
import java.io.IOException;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonMappingException;
public class Graph {
private int nodes;
private int edges;
private Tree[] trees;
public Graph(Input jsonGraph) throws JsonParseException, JsonMappingException, IOException {
nodes = jsonGraph.getNodes();
trees = (Tree[]) new Tree[nodes];
for (int i = 0; i < nodes; i++) {
trees[i] = new Tree();
}
int edgesFromInput = jsonGraph.getEdges();
for (int i = 0; i < edgesFromInput; i++) {
int first = jsonGraph.getEdgeList()
.get(i)
.getFirst();
int second = jsonGraph.getEdgeList()
.get(i)
.getSecond();
int weight = jsonGraph.getEdgeList()
.get(i)
.getWeight();
Edge edge = new Edge(first, second, weight);
trees[first].addEdge(edge);
trees[second].addEdge(edge);
edges++;
}
}
public int getNodes() {
return nodes;
}
public int getEdges() {
return edges;
}
public Iterable<Edge> iterableTree(int i) {
return trees[i];
}
public Iterable<Edge> getAllEdges() {
Iterable<Edge> list = new Tree();
for (int i = 0; i < nodes; i++) {
for (Edge edge : iterableTree(i)) {
if (edge.getOtherNode(i) > i) {
((Tree) list).addEdge(edge);
}
}
}
return list;
}
}
algorithms-miscellaneous-5/src/main/java/com/baeldung/algorithms/boruvka/Input.java
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@@ -0,0 +1,65 @@
package com.baeldung.algorithms.boruvka;
import java.util.List;
public class Input {
private int nodes;
private int edges;
private List<E> edgeList;
public int getNodes() {
return nodes;
}
public void setNodes(int nodes) {
this.nodes = nodes;
}
public int getEdges() {
return edges;
}
public void setEdges(int edges) {
this.edges = edges;
}
public List<E> getEdgeList() {
return edgeList;
}
public void setEdgeList(List<E> edgeList) {
this.edgeList = edgeList;
}
static class E {
private int first;
private int second;
private int weight;
public int getFirst() {
return first;
}
public void setFirst(int first) {
this.first = first;
}
public int getSecond() {
return second;
}
public void setSecond(int second) {
this.second = second;
}
public int getWeight() {
return weight;
}
public void setWeight(int weight) {
this.weight = weight;
}
}
}
algorithms-miscellaneous-5/src/main/java/com/baeldung/algorithms/boruvka/Tree.java
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@@ -0,0 +1,63 @@
package com.baeldung.algorithms.boruvka;
import java.util.Iterator;
public class Tree implements Iterable<Edge> {
private Node root;
private int edgeCount;
private static class Node {
private Edge edge;
private Node next;
public String toString() {
String nextStr = next != null ? next.toString() : "";
return edge.toString() + " | " + nextStr;
}
}
public Tree() {
root = null;
edgeCount = 0;
}
public int getEdgeCount() {
return edgeCount;
}
public void addEdge(Edge edge) {
Node oldRoot = root;
root = new Node();
root.edge = edge;
root.next = oldRoot;
edgeCount++;
}
public String toString() {
String rootStr = root != null ? root.toString() : "";
return "Tree: " + rootStr + "Size: " + edgeCount;
}
public Iterator<Edge> iterator() {
return new LinkedIterator(root);
}
private class LinkedIterator implements Iterator<Edge> {
private Node current;
public LinkedIterator(Node root) {
current = root;
}
public boolean hasNext() {
return current != null;
}
public Edge next() {
Edge edge = current.edge;
current = current.next;
return edge;
}
}
}
algorithms-miscellaneous-5/src/test/java/com/baeldung/algorithms/balancedbinarytree/AVLTreeUnitTest.java
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@@ -0,0 +1,83 @@
package com.baeldung.algorithms.balancedbinarytree;
import org.junit.Assert;
import org.junit.Test;
public class AVLTreeUnitTest {
@Test
public void givenEmptyTree_whenHeightCalled_shouldReturnMinus1() {
AVLTree tree = new AVLTree();
Assert.assertEquals(-1, tree.height());
}
@Test
public void givenEmptyTree_whenInsertCalled_heightShouldBeZero() {
AVLTree tree = new AVLTree();
tree.insert(1);
Assert.assertEquals(0, tree.height());
}
@Test
public void givenEmptyTree_whenInsertCalled_treeShouldBeAvl() {
AVLTree tree = new AVLTree();
tree.insert(1);
Assert.assertTrue(isAVL(tree));
}
@Test
public void givenSampleTree_whenInsertCalled_treeShouldBeAvl() {
AVLTree tree = getSampleAVLTree();
int newKey = 11;
tree.insert(newKey);
Assert.assertTrue(isAVL(tree));
}
@Test
public void givenSampleTree_whenFindExistingKeyCalled_shouldReturnMatchedNode() {
AVLTree tree = getSampleAVLTree();
int existingKey = 2;
AVLTree.Node result = tree.find(existingKey);
Assert.assertEquals(result.key, existingKey);
}
@Test
public void givenSampleTree_whenFindNotExistingKeyCalled_shouldReturnNull() {
AVLTree tree = getSampleAVLTree();
int notExistingKey = 11;
AVLTree.Node result = tree.find(notExistingKey);
Assert.assertNull(result);
}
@Test
public void givenEmptyTree_whenDeleteCalled_treeShouldBeAvl() {
AVLTree tree = new AVLTree();
tree.delete(1);
Assert.assertTrue(isAVL(tree));
}
@Test
public void givenSampleTree_whenDeleteCalled_treeShouldBeAvl() {
AVLTree tree = getSampleAVLTree();
tree.delete(1);
Assert.assertTrue(isAVL(tree, tree.getRoot()));
}
private boolean isAVL(AVLTree tree) {
return isAVL(tree, tree.getRoot());
}
private boolean isAVL(AVLTree tree, AVLTree.Node node) {
if ( node == null )
return true;
int balance = tree.getBalance(node);
return (balance <= 1 && balance >= -1) && isAVL(tree, node.left) && isAVL(tree, node.right);
}
private AVLTree getSampleAVLTree() {
AVLTree avlTree = new AVLTree();
for (int i = 0; i < 10; i++)
avlTree.insert(i);
return avlTree;
}
}
algorithms-miscellaneous-5/src/test/java/com/baeldung/algorithms/boruvka/BoruvkaUnitTest.java
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@@ -0,0 +1,48 @@
package com.baeldung.algorithms.boruvka;
import static org.junit.jupiter.api.Assertions.assertEquals;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import org.junit.Before;
import org.junit.Test;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;
public class BoruvkaUnitTest {
private Input input;
private static String INPUT_JSON = "/input.json";
@Before
public void convertInputJsonToObject() throws JsonParseException, JsonMappingException, IOException {
ObjectMapper mapper = new ObjectMapper();
StringBuilder jsonStr = new StringBuilder();
try (BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(BoruvkaMST.class.getResourceAsStream(INPUT_JSON)))) {
String line;
while ((line = bufferedReader.readLine()) != null) {
jsonStr.append(line)
.append("\n");
}
}
input = mapper.readValue(jsonStr.toString(), Input.class);
}
@Test
public void givenInputGraph_whenBoruvkaPerformed_thenMinimumSpanningTree() throws JsonParseException, JsonMappingException, IOException {
Graph graph = new Graph(input);
BoruvkaMST boruvkaMST = new BoruvkaMST(graph);
Tree mst = (Tree) boruvkaMST.getMST();
assertEquals(30, boruvkaMST.getTotalWeight());
assertEquals(4, mst.getEdgeCount());
}
}
algorithms-miscellaneous-5/src/test/resources/input.json
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@@ -0,0 +1,41 @@
{
"nodes": 5,
"edges": 7,
"edgeList": [
{
"first": 0,
"second": 1,
"weight": 8
},
{
"first": 0,
"second": 2,
"weight": 5
},
{
"first": 1,
"second": 2,
"weight": 9
},
{
"first": 1,
"second": 3,
"weight": 11
},
{
"first": 2,
"second": 3,
"weight": 15
},
{
"first": 2,
"second": 4,
"weight": 10
},
{
"first": 3,
"second": 4,
"weight": 7
}
]
}
algorithms-searching/src/main/java/com/baeldung/algorithms/suffixtree/Node.java
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@@ -0,0 +1,57 @@
package com.baeldung.algorithms.suffixtree;
import java.util.ArrayList;
import java.util.List;
public class Node {
private String text;
private List<Node> children;
private int position;
public Node(String word, int position) {
this.text = word;
this.position = position;
this.children = new ArrayList<>();
}
public String getText() {
return text;
}
public void setText(String text) {
this.text = text;
}
public int getPosition() {
return position;
}
public void setPosition(int position) {
this.position = position;
}
public List<Node> getChildren() {
return children;
}
public void setChildren(List<Node> children) {
this.children = children;
}
public String printTree(String depthIndicator) {
String str = "";
String positionStr = position > -1 ? "[" + String.valueOf(position) + "]" : "";
str += depthIndicator + text + positionStr + "\n";
for (int i = 0; i < children.size(); i++) {
str += children.get(i)
.printTree(depthIndicator + "\t");
}
return str;
}
@Override
public String toString() {
return printTree("");
}
}
algorithms-searching/src/main/java/com/baeldung/algorithms/suffixtree/SuffixTree.java
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@@ -0,0 +1,175 @@
package com.baeldung.algorithms.suffixtree;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class SuffixTree {
private static final Logger LOGGER = LoggerFactory.getLogger(SuffixTree.class);
private static final String WORD_TERMINATION = "$";
private static final int POSITION_UNDEFINED = -1;
private Node root;
private String fullText;
public SuffixTree(String text) {
root = new Node("", POSITION_UNDEFINED);
for (int i = 0; i < text.length(); i++) {
addSuffix(text.substring(i) + WORD_TERMINATION, i);
}
fullText = text;
}
public List<String> searchText(String pattern) {
LOGGER.info("Searching for pattern \"{}\"", pattern);
List<String> result = new ArrayList<>();
List<Node> nodes = getAllNodesInTraversePath(pattern, root, false);
if (nodes.size() > 0) {
Node lastNode = nodes.get(nodes.size() - 1);
if (lastNode != null) {
List<Integer> positions = getPositions(lastNode);
positions = positions.stream()
.sorted()
.collect(Collectors.toList());
positions.forEach(m -> result.add((markPatternInText(m, pattern))));
}
}
return result;
}
private void addSuffix(String suffix, int position) {
LOGGER.info(">>>>>>>>>>>> Adding new suffix {}", suffix);
List<Node> nodes = getAllNodesInTraversePath(suffix, root, true);
if (nodes.size() == 0) {
addChildNode(root, suffix, position);
LOGGER.info("{}", printTree());
} else {
Node lastNode = nodes.remove(nodes.size() - 1);
String newText = suffix;
if (nodes.size() > 0) {
String existingSuffixUptoLastNode = nodes.stream()
.map(a -> a.getText())
.reduce("", String::concat);
// Remove prefix from newText already included in parent
newText = newText.substring(existingSuffixUptoLastNode.length());
}
extendNode(lastNode, newText, position);
LOGGER.info("{}", printTree());
}
}
private List<Integer> getPositions(Node node) {
List<Integer> positions = new ArrayList<>();
if (node.getText()
.endsWith(WORD_TERMINATION)) {
positions.add(node.getPosition());
}
for (int i = 0; i < node.getChildren()
.size(); i++) {
positions.addAll(getPositions(node.getChildren()
.get(i)));
}
return positions;
}
private String markPatternInText(Integer startPosition, String pattern) {
String matchingTextLHS = fullText.substring(0, startPosition);
String matchingText = fullText.substring(startPosition, startPosition + pattern.length());
String matchingTextRHS = fullText.substring(startPosition + pattern.length());
return matchingTextLHS + "[" + matchingText + "]" + matchingTextRHS;
}
private void addChildNode(Node parentNode, String text, int position) {
parentNode.getChildren()
.add(new Node(text, position));
}
private void extendNode(Node node, String newText, int position) {
String currentText = node.getText();
String commonPrefix = getLongestCommonPrefix(currentText, newText);
if (commonPrefix != currentText) {
String parentText = currentText.substring(0, commonPrefix.length());
String childText = currentText.substring(commonPrefix.length());
splitNodeToParentAndChild(node, parentText, childText);
}
String remainingText = newText.substring(commonPrefix.length());
addChildNode(node, remainingText, position);
}
private void splitNodeToParentAndChild(Node parentNode, String parentNewText, String childNewText) {
Node childNode = new Node(childNewText, parentNode.getPosition());
if (parentNode.getChildren()
.size() > 0) {
while (parentNode.getChildren()
.size() > 0) {
childNode.getChildren()
.add(parentNode.getChildren()
.remove(0));
}
}
parentNode.getChildren()
.add(childNode);
parentNode.setText(parentNewText);
parentNode.setPosition(POSITION_UNDEFINED);
}
private String getLongestCommonPrefix(String str1, String str2) {
int compareLength = Math.min(str1.length(), str2.length());
for (int i = 0; i < compareLength; i++) {
if (str1.charAt(i) != str2.charAt(i)) {
return str1.substring(0, i);
}
}
return str1.substring(0, compareLength);
}
private List<Node> getAllNodesInTraversePath(String pattern, Node startNode, boolean isAllowPartialMatch) {
List<Node> nodes = new ArrayList<>();
for (int i = 0; i < startNode.getChildren()
.size(); i++) {
Node currentNode = startNode.getChildren()
.get(i);
String nodeText = currentNode.getText();
if (pattern.charAt(0) == nodeText.charAt(0)) {
if (isAllowPartialMatch && pattern.length() <= nodeText.length()) {
nodes.add(currentNode);
return nodes;
}
int compareLength = Math.min(nodeText.length(), pattern.length());
for (int j = 1; j < compareLength; j++) {
if (pattern.charAt(j) != nodeText.charAt(j)) {
if (isAllowPartialMatch) {
nodes.add(currentNode);
}
return nodes;
}
}
nodes.add(currentNode);
if (pattern.length() > compareLength) {
List<Node> nodes2 = getAllNodesInTraversePath(pattern.substring(compareLength), currentNode, isAllowPartialMatch);
if (nodes2.size() > 0) {
nodes.addAll(nodes2);
} else if (!isAllowPartialMatch) {
nodes.add(null);
}
}
return nodes;
}
}
return nodes;
}
public String printTree() {
return root.printTree("");
}
}
algorithms-searching/src/test/java/com/baeldung/algorithms/suffixtree/SuffixTreeUnitTest.java
+77
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@@ -0,0 +1,77 @@
package com.baeldung.algorithms.suffixtree;
import java.util.List;
import org.junit.Assert;
import org.junit.BeforeClass;
import org.junit.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class SuffixTreeUnitTest {
private static final Logger LOGGER = LoggerFactory.getLogger(SuffixTreeUnitTest.class);
private static SuffixTree suffixTree;
@BeforeClass
public static void setUp() {
suffixTree = new SuffixTree("havanabanana");
printTree();
}
@Test
public void givenSuffixTree_whenSearchingForA_thenReturn6Matches() {
List<String> matches = suffixTree.searchText("a");
matches.stream()
.forEach(m -> LOGGER.info(m));
Assert.assertArrayEquals(new String[] { "h[a]vanabanana", "hav[a]nabanana", "havan[a]banana", "havanab[a]nana", "havanaban[a]na", "havanabanan[a]" }, matches.toArray());
}
@Test
public void givenSuffixTree_whenSearchingForNab_thenReturn1Match() {
List<String> matches = suffixTree.searchText("nab");
matches.stream()
.forEach(m -> LOGGER.info(m));
Assert.assertArrayEquals(new String[] { "hava[nab]anana" }, matches.toArray());
}
@Test
public void givenSuffixTree_whenSearchingForNag_thenReturnNoMatches() {
List<String> matches = suffixTree.searchText("nag");
matches.stream()
.forEach(m -> LOGGER.info(m));
Assert.assertArrayEquals(new String[] {}, matches.toArray());
}
@Test
public void givenSuffixTree_whenSearchingForBanana_thenReturn2Matches() {
List<String> matches = suffixTree.searchText("ana");
matches.stream()
.forEach(m -> LOGGER.info(m));
Assert.assertArrayEquals(new String[] { "hav[ana]banana", "havanab[ana]na", "havanaban[ana]" }, matches.toArray());
}
@Test
public void givenSuffixTree_whenSearchingForNa_thenReturn4Matches() {
List<String> matches = suffixTree.searchText("na");
matches.stream()
.forEach(m -> LOGGER.info(m));
Assert.assertArrayEquals(new String[] { "hava[na]banana", "havanaba[na]na", "havanabana[na]" }, matches.toArray());
}
@Test
public void givenSuffixTree_whenSearchingForX_thenReturnNoMatches() {
List<String> matches = suffixTree.searchText("x");
matches.stream()
.forEach(m -> LOGGER.info(m));
Assert.assertArrayEquals(new String[] {}, matches.toArray());
}
private static void printTree() {
suffixTree.printTree();
LOGGER.info("\n" + suffixTree.printTree());
LOGGER.info("==============================================");
}
}
algorithms-sorting-2/README.md
+3
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@@ -0,0 +1,3 @@
### Relevant Articles:
- [Partitioning and Sorting Arrays with Many Repeated Entries](https://www.baeldung.com/java-sorting-arrays-with-repeated-entries)
apache-beam/pom.xml
+43
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@@ -0,0 +1,43 @@
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>com.baeldung</groupId>
<artifactId>parent-modules</artifactId>
<version>1.0.0-SNAPSHOT</version>
</parent>
<groupId>com.baeldung.apache</groupId>
<artifactId>apache-beam</artifactId>
<version>0.0.1-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>org.apache.beam</groupId>
<artifactId>beam-sdks-java-core</artifactId>
<version>${beam.version}</version>
</dependency>
<!-- runtime scoped -->
<dependency>
<groupId>org.apache.beam</groupId>
<artifactId>beam-runners-direct-java</artifactId>
<version>${beam.version}</version>
<scope>runtime</scope>
</dependency>
<!-- test scoped -->
<dependency>
<groupId>org.assertj</groupId>
<artifactId>assertj-core</artifactId>
<version>${assertj.version}</version>
<scope>test</scope>
</dependency>
</dependencies>
<properties>
<beam.version>2.19.0</beam.version>
<assertj.version>3.6.1</assertj.version>
</properties>
</project>
apache-beam/src/main/java/com/baeldung/apache/beam/intro/WordCount.java
+71
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@@ -0,0 +1,71 @@
package com.baeldung.apache.beam.intro;
import java.util.Arrays;
import org.apache.beam.sdk.Pipeline;
import org.apache.beam.sdk.io.TextIO;
import org.apache.beam.sdk.options.PipelineOptions;
import org.apache.beam.sdk.options.PipelineOptionsFactory;
import org.apache.beam.sdk.transforms.Count;
import org.apache.beam.sdk.transforms.Filter;
import org.apache.beam.sdk.transforms.FlatMapElements;
import org.apache.beam.sdk.transforms.MapElements;
import org.apache.beam.sdk.values.KV;
import org.apache.beam.sdk.values.PCollection;
import org.apache.beam.sdk.values.TypeDescriptors;
public class WordCount {
public static boolean wordCount(String inputFilePath, String outputFilePath) {
// We use default options
PipelineOptions options = PipelineOptionsFactory.create();
// to create the pipeline
Pipeline p = Pipeline.create(options);
// Here is our workflow graph
PCollection<KV<String, Long>> wordCount = p
.apply("(1) Read all lines", TextIO.read().from(inputFilePath))
.apply("(2) Flatmap to a list of words", FlatMapElements.into(TypeDescriptors.strings())
.via(line -> Arrays.asList(line.split("\\s"))))
.apply("(3) Lowercase all", MapElements.into(TypeDescriptors.strings())
.via(word -> word.toLowerCase()))
.apply("(4) Trim punctuations", MapElements.into(TypeDescriptors.strings())
.via(word -> trim(word)))
.apply("(5) Filter stopwords", Filter.by(word -> !isStopWord(word)))
.apply("(6) Count words", Count.perElement());
// We convert the PCollection to String so that we can write it to file
wordCount.apply(MapElements.into(TypeDescriptors.strings())
.via(count -> count.getKey() + " --> " + count.getValue()))
.apply(TextIO.write().to(outputFilePath));
// Finally we must run the pipeline, otherwise it's only a definition
p.run().waitUntilFinish();
return true;
}
public static boolean isStopWord(String word) {
String[] stopwords = {"am", "are", "is", "i", "you", "me",
"he", "she", "they", "them", "was",
"were", "from", "in", "of", "to", "be",
"him", "her", "us", "and", "or"};
for (String stopword : stopwords) {
if (stopword.compareTo(word) == 0) {
return true;
}
}
return false;
}
public static String trim(String word) {
return word.replace("(","")
.replace(")", "")
.replace(",", "")
.replace(".", "")
.replace("\"", "")
.replace("'", "")
.replace(":", "")
.replace(";", "")
.replace("-", "")
.replace("?", "")
.replace("!", "");
}
}
apache-beam/src/test/java/com/baeldung/apache/beam/intro/WordCountUnitTest.java
+19
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@@ -0,0 +1,19 @@
package com.baeldung.apache.beam.intro;
import static org.junit.Assert.assertTrue;
import org.junit.Ignore;
import org.junit.Test;
import com.baeldung.apache.beam.intro.WordCount;
public class WordCountUnitTest {
@Test
// @Ignore
public void givenInputFile_whenWordCountRuns_thenJobFinishWithoutError() {
boolean jobDone = WordCount.wordCount("src/test/resources/wordcount.txt", "target/output");
assertTrue(jobDone);
}
}
apache-beam/src/test/resources/wordcount.txt
+16
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@@ -0,0 +1,16 @@
We've all heard the scare stories about North Korea: the homemade nuclear arsenal built while their people starve and then aimed imprecisely at the rest of the world, a
leader so deluded he makes L Ron Hubbard look like a man excessively overburdened with self-doubt and their deep-seated belief that foreign capitalists will invade at any
moment and steal all their bauxite.
The popular portrayal of this Marxist nation is something like one of the more harrowing episodes of M*A*S*H, only with the cast of wacky characters replaced by twitchy,
heavily armed Stalinist meth addicts
Cracked would like to take a moment to celebrate the good things about North Korea though, the things that the country's enemies prefer to suppress as part of their politically
motivated jealousy. Like how no different to you and me, there's nothing every North Korean likes more after an 18 hour shift at the phosphorus plant than a nice beer to go with
his dried fish ration. Ever attentive to its people's needs and in the twinkling of a decade, North Korea's leadership bought, disassembled, transported and rebuilt a British
brewery in order to discover and reproduce the secrets of beer and then brew the sweet nectar for its hardworking people, up to 18 bottles at a time. And with minimal fatalities.
When was the last time YOUR leader got a beer for YOU, American? (NB do not answer this question if you are Henry Louis Gates).
Or how about the fried chicken restaurant that downtown Pyongyang boasts? Yes real chicken, fried and then delivered to your sleeping cube, with optional beer if you like! You
don't even have to remove the feathers or pull out the gizzard yourself. Mostly. Americans must eat their fried chicken from a bucket, like swine, sold by a company so secretive
that even the very blend of seasoning used is intentionally kept from them. And they call North Korea paranoid?
And how many nations would entertain the syphilitic, bourgeois ramblings of Bill Clinton let alone permit him anywhere near their proud womenfolk? Only wise Kim Jong Il could see
past Bill's many, many imperfections and treat him with the pity and kindness he deserves, accepting his feeble pleas to pardon the American spies rightly convicted of photographing
the nation's sensitive beetroot fields.
apache-poi/README.md
+3
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@@ -6,3 +6,6 @@ This module contains articles about Apache POI
- [Microsoft Word Processing in Java with Apache POI](https://www.baeldung.com/java-microsoft-word-with-apache-poi)
- [Working with Microsoft Excel in Java](https://www.baeldung.com/java-microsoft-excel)
- [Creating a MS PowerPoint Presentation in Java](https://www.baeldung.com/apache-poi-slideshow)
- [Merge Cells in Excel Using Apache POI](https://www.baeldung.com/java-apache-poi-merge-cells)
- [Get String Value of Excel Cell with Apache POI](https://www.baeldung.com/java-apache-poi-cell-string-value)
- [Read Excel Cell Value Rather Than Formula With Apache POI](https://github.com/eugenp/tutorials/tree/master/apache-poi)
apache-poi/src/test/java/com/baeldung/poi/excel/merge/ExcelCellMergerUnitTest.java
+53
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@@ -0,0 +1,53 @@
package com.baeldung.poi.excel.merge;
import static org.junit.Assert.assertEquals;
import java.io.IOException;
import java.net.URISyntaxException;
import java.nio.file.Paths;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.util.CellRangeAddress;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.junit.Before;
import org.junit.Test;
public class ExcelCellMergerUnitTest {
private static final String FILE_NAME = "ExcelCellFormatterTest.xlsx";
private String fileLocation;
@Before
public void setup() throws IOException, URISyntaxException {
fileLocation = Paths.get(ClassLoader.getSystemResource(FILE_NAME).toURI()).toString();
}
@Test
public void givenCellIndex_whenAddMergeRegion_thenMergeRegionCreated() throws IOException {
Workbook workbook = new XSSFWorkbook(fileLocation);
Sheet sheet = workbook.getSheetAt(0);
assertEquals(0, sheet.getNumMergedRegions());
int firstRow = 0;
int lastRow = 0;
int firstCol = 0;
int lastCol = 2;
sheet.addMergedRegion(new CellRangeAddress(firstRow, lastRow, firstCol, lastCol));
assertEquals(1, sheet.getNumMergedRegions());
workbook.close();
}
@Test
public void givenCellRefString_whenAddMergeRegion_thenMergeRegionCreated() throws IOException {
Workbook workbook = new XSSFWorkbook(fileLocation);
Sheet sheet = workbook.getSheetAt(0);
assertEquals(0, sheet.getNumMergedRegions());
sheet.addMergedRegion(CellRangeAddress.valueOf("A1:C1"));
assertEquals(1, sheet.getNumMergedRegions());
workbook.close();
}
}
apache-rocketmq/README.md
+2
View File
@@ -3,3 +3,5 @@
This module contains articles about Apache RocketMQ
### Relevant Articles:
- [Apache RocketMQ with Spring Boot](https://www.baeldung.com/apache-rocketmq-spring-boot)
apache-spark/README.md
+1 -1
View File
@@ -7,4 +7,4 @@ This module contains articles about Apache Spark
- [Introduction to Apache Spark](https://www.baeldung.com/apache-spark)
- [Building a Data Pipeline with Kafka, Spark Streaming and Cassandra](https://www.baeldung.com/kafka-spark-data-pipeline)
- [Machine Learning with Spark MLlib](https://www.baeldung.com/spark-mlib-machine-learning)
- [Introduction to Spark Graph Processing with GraphFrames](https://www.baeldung.com/spark-graph-graphframes)
apache-tapestry/README.md
+3
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@@ -0,0 +1,3 @@
### Relevant Articles
- [Intro to Apache Tapestry](https://www.baeldung.com/apache-tapestry)
aws-reactive/README.md
+3
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@@ -0,0 +1,3 @@
### Relevant Articles:
- [AWS S3 with Java – Reactive Support](https://www.baeldung.com/java-aws-s3-reactive)
blade/pom.xml
+1 -1
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@@ -106,7 +106,7 @@
<arguments>
<argument>java</argument>
<argument>-jar</argument>
<argument>sample-blade-app.jar</argument>
<argument>blade.jar</argument>
</arguments>
</configuration>
</execution>

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