Created 2 modules: parsley-grammar and parsley-examples

parsley-examples/pom.xml

@@ -0,0 +1,83 @@
+<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/maven-v4_0_0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <artifactId>parsley-examples</artifactId>
+  <packaging>jar</packaging>
+  <version>0.1.0-SNAPSHOT</version>
+
+  <name>parsley-examples</name>
+  <parent>
+    <groupId>com.albertoventurini.parsley</groupId>
+    <artifactId>parsley</artifactId>
+    <version>0.1.0-SNAPSHOT</version>
+  </parent>
+
+  <url>https://github.com/albertoventurini/parsley</url>
+
+  <properties>
+    <antlr.version>4.7.1</antlr.version>
+    <junit.version>5.6.1</junit.version>
+    <maven-compiler-plugin.version>3.8.1</maven-compiler-plugin.version>
+    <maven-surefire-plugin.version>3.0.0-M5</maven-surefire-plugin.version>
+    <maven-jar-plugin.version>3.2.0</maven-jar-plugin.version>
+    <maven-shade.plugin.version>3.2.2</maven-shade.plugin.version>
+    <mainClass>com.albertoventurini.parsley.Main</mainClass>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter</artifactId>
+      <scope>test</scope>
+    </dependency>
+
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter-engine</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>com.albertoventurini.parsley</groupId>
+      <artifactId>parsley-grammar</artifactId>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>${maven-compiler-plugin.version}</version>
+        <configuration>
+          <source>11</source>
+          <target>11</target>
+          <release>11</release>
+        </configuration>
+      </plugin>
+
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-surefire-plugin</artifactId>
+        <version>${maven-surefire-plugin.version}</version>
+        <configuration>
+          <argLine>--enable-preview</argLine>
+        </configuration>
+      </plugin>
+
+      <plugin>
+        <artifactId>maven-jar-plugin</artifactId>
+        <configuration>
+          <archive>
+            <manifest>
+              <addClasspath>true</addClasspath>
+              <mainClass>${mainClass}</mainClass>
+            </manifest>
+          </archive>
+        </configuration>
+      </plugin>
+    </plugins>
+
+  </build>
+
+</project>

parsley-examples/src/main/java/com/albertoventurini/parsley/examples/graphml/Edge.java

@@ -0,0 +1,38 @@
+package com.albertoventurini.parsley.examples.graphml;
+
+import java.util.Map;
+
+public final class Edge {
+
+    private final String id;
+    private final String source;
+    private final String target;
+    private final Map<String, String> data;
+
+    public Edge(
+            final String id,
+            final String source,
+            final String target,
+            final Map<String, String> data) {
+        this.id = id;
+        this.source = source;
+        this.target = target;
+        this.data = data;
+    }
+
+    public String id() {
+        return id;
+    }
+
+    public String source() {
+        return source;
+    }
+
+    public String target() {
+        return target;
+    }
+
+    public Map<String, String> data() {
+        return data;
+    }
+}

parsley-examples/src/main/java/com/albertoventurini/parsley/examples/graphml/GrammarGraphMLParser.java

@@ -0,0 +1,150 @@
+package com.albertoventurini.parsley.examples.graphml;
+
+import com.albertoventurini.parsley.grammar.Grammar;
+import com.albertoventurini.parsley.grammar.ParseTree;
+import com.albertoventurini.parsley.grammar.rules.Rule;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.List;
+import java.util.Map;
+import java.util.function.BiFunction;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+
+import static com.albertoventurini.parsley.grammar.Grammar.*;
+
+public class GrammarGraphMLParser implements GraphMLParser {
+
+    private final Grammar grammar;
+
+    public GrammarGraphMLParser() {
+
+        final Rule comment = sequence(string("<!--"), until("-->")).as("comment");
+        final Rule comments = zeroOrMore(comment).as("comments");
+
+        final Rule xmlHeader = string("<?xml version='1.0' ?>").as("header");
+
+        final Rule attribute = sequence(
+                takeWhile(c -> c != '=' && c != '>'),
+                character('='),
+                character('\''),
+                takeWhile(c -> c != '\''),
+                character('\'')).as("attribute");
+
+        final Function<String, Rule> tagFunc = (s) -> sequence(
+                character('<'),
+                string(s).as("tagName"),
+                zeroOrMore(attribute).as("attributes"),
+                character('>')).as("tag:" + s);
+
+        final Function<String, Rule> closingTagFunc = (s) -> sequence(
+                string("</"),
+                string(s),
+                character('>')).as("closingTag:" + s);
+
+        final BiFunction<String, Rule, Rule> elementFunc = (tagName, content) -> sequence(
+                tagFunc.apply(tagName).as("tag:" + tagName),
+                content.as("content"),
+                closingTagFunc.apply(tagName).as("closingTag:" + tagName));
+
+        final Rule data = elementFunc.apply("data", takeWhile(c -> c != '<')).as("dataElem");
+
+        final Rule node = elementFunc.apply("node", zeroOrMore(data)).as("nodeElem");
+
+        final Rule edge = elementFunc.apply("edge", zeroOrMore(data)).as("edgeElem");
+
+        final Rule graph = sequence(
+                tagFunc.apply("graph"),
+                oneOrMore(node).as("nodes"),
+                oneOrMore(edge).as("edges"),
+                closingTagFunc.apply("graph")).as("graphElem");
+
+        final Rule key = sequence(tagFunc.apply("key"), closingTagFunc.apply("key"))
+                .as("keyElem");
+
+        final Rule graphml = sequence(
+                tagFunc.apply("graphml"),
+                oneOrMore(key).as("keys"),
+                graph,
+                closingTagFunc.apply("graphml")).as("graphmlElem");
+
+        final Rule graphmlFile = sequence(
+                xmlHeader,
+                comments.discard(),
+                graphml).as("graphmlFile");
+
+        grammar = new Grammar(graphmlFile, null);
+    }
+
+    @Override
+    public GraphMLParseResult parse(final String filePath) {
+        try {
+             return grammar
+                     .parse(Files.readString(Path.of(filePath)))
+                     .map(this::processParseTree)
+                     .orElseThrow(() -> new RuntimeException("Unable to parse graphml file: " + filePath));
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private GraphMLParseResult processParseTree(final ParseTree parseTree) {
+
+        final List<Node> nodes = parseTree.getFirstDescendantByName("nodes").map(n ->
+            n.getChildren()
+                    .stream()
+                    .map(this::processNodeElem)
+                    .collect(Collectors.toList())
+        ).orElseThrow();
+
+        final List<Edge> edges = parseTree.getFirstDescendantByName("edges").map(n ->
+                n.getChildren()
+                        .stream()
+                        .map(this::processEdgeElem)
+                        .collect(Collectors.toList())
+        ).orElseThrow();
+
+        return new GraphMLParseResult(nodes, edges);
+    }
+
+    private Node processNodeElem(final ParseTree nodeElem) {
+        final String id = extractAttribute(nodeElem.child("tag:node"), "id");
+
+        final Map<String, String> data = nodeElem.child("content").getChildren()
+                .stream()
+                .map(this::extractDataElemContent)
+                .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
+
+        return new Node(id, data);
+    }
+
+    private Edge processEdgeElem(final ParseTree edgeElem) {
+        final String id = extractAttribute(edgeElem.child("tag:edge"), "id");
+        final String source = extractAttribute(edgeElem.child("tag:edge"), "source");
+        final String target = extractAttribute(edgeElem.child("tag:edge"), "target");
+
+        final Map<String, String> data = edgeElem.child("content").getChildren()
+                .stream()
+                .map(this::extractDataElemContent)
+                .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
+
+        return new Edge(id, source, target, data);
+    }
+
+    private Map.Entry<String, String> extractDataElemContent(final ParseTree dataElem) {
+        final var attribute = extractAttribute(dataElem.child("tag:data"), "key");
+        final var content = dataElem.child(1).getText();
+        return Map.entry(attribute, content);
+    }
+
+    private String extractAttribute(final ParseTree tag, final String attributeKey) {
+        return tag.child("attributes").getChildren()
+                .stream()
+                .filter(a -> a.child(0).getText().equals(attributeKey))
+                .map(a -> a.child(1).getText())
+                .findFirst()
+                .orElseThrow();
+    }
+}

parsley-examples/src/main/java/com/albertoventurini/parsley/examples/graphml/GraphMLParseResult.java

@@ -0,0 +1,22 @@
+package com.albertoventurini.parsley.examples.graphml;
+
+import java.util.List;
+
+public final class GraphMLParseResult {
+
+    private final List<Node> nodes;
+    private final List<Edge> edges;
+
+    public GraphMLParseResult(final List<Node> nodes, final List<Edge> edges) {
+        this.nodes = nodes;
+        this.edges = edges;
+    }
+
+    public List<Node> nodes() {
+        return nodes;
+    }
+
+    public List<Edge> edges() {
+        return edges;
+    }
+}

parsley-examples/src/main/java/com/albertoventurini/parsley/examples/graphml/GraphMLParser.java

@@ -0,0 +1,5 @@
+package com.albertoventurini.parsley.examples.graphml;
+
+public interface GraphMLParser {
+    GraphMLParseResult parse(String filePath);
+}

parsley-examples/src/main/java/com/albertoventurini/parsley/examples/graphml/Node.java

@@ -0,0 +1,22 @@
+package com.albertoventurini.parsley.examples.graphml;
+
+import java.util.Map;
+
+public final class Node {
+
+    private final String id;
+    private final Map<String, String> data;
+
+    public Node(final String id, final Map<String, String> data) {
+        this.id = id;
+        this.data = data;
+    }
+
+    public String id() {
+        return id;
+    }
+
+    public Map<String, String> data() {
+        return data;
+    }
+}

parsley-examples/src/test/java/com/albertoventurini/parsley/examples/graphml/GraphMLGrammarTest.java

@@ -0,0 +1,90 @@
+package com.albertoventurini.parsley.examples.graphml;
+
+import com.albertoventurini.parsley.grammar.Grammar;
+import com.albertoventurini.parsley.grammar.rules.Rule;
+import org.junit.jupiter.api.Test;
+
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.function.BiFunction;
+import java.util.function.Function;
+
+import static com.albertoventurini.parsley.grammar.Grammar.*;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class GraphMLGrammarTest {
+
+    private final Grammar grammar;
+
+    public GraphMLGrammarTest() {
+        final Rule comment = sequence(string("<!--"), until("-->"));
+        final Rule comments = zeroOrMore(comment);
+
+        final Rule xmlHeader = string("<?xml version='1.0' ?>").as("header");
+
+        final Rule attribute = sequence(
+                takeWhile(c -> c != '=' && c != '>'),
+                character('='),
+                character('\''),
+                takeWhile(c -> c != '\''),
+                character('\'')).as("attribute");
+
+        final Function<String, Rule> tagFunc = (s) -> sequence(
+                character('<'),
+                string(s),
+                zeroOrMore(attribute).as("attributes"),
+                character('>'));
+
+        final Function<String, Rule> closingTagFunc = (s) -> sequence(
+                string("</"),
+                string(s),
+                character('>'));
+
+        final BiFunction<String, Rule, Rule> elementFunc = (tagName, content) -> sequence(
+                tagFunc.apply(tagName).as("tag:" + tagName),
+                content.as("content"),
+                closingTagFunc.apply(tagName).as("closingTag:" + tagName));
+
+        final Rule data = elementFunc.apply("data", takeWhile(c -> c != '<')).as("dataElem");
+
+        final Rule node = elementFunc.apply("node", zeroOrMore(data)).as("nodeElem");
+
+        final Rule edge = elementFunc.apply("edge", zeroOrMore(data)).as("edgeElem");
+
+        final Rule graph = sequence(
+                tagFunc.apply("graph"),
+                oneOrMore(node).as("nodes"),
+                oneOrMore(edge).as("edges"),
+                closingTagFunc.apply("graph")).as("graphElem");
+
+        final Rule key = sequence(
+                tagFunc.apply("key"),
+                closingTagFunc.apply("key")).as("keyElem");
+
+        final Rule graphml = sequence(
+                tagFunc.apply("graphml"),
+                oneOrMore(key).as("keys"),
+                graph,
+                closingTagFunc.apply("graphml")).as("graphmlElem");
+
+        final Rule graphmlFile = sequence(xmlHeader, graphml).as("graphmlFile");
+
+        grammar = new Grammar(graphmlFile, comments);
+    }
+
+    @Test
+    public void graphmlGrammar_shouldParseGraphmlFile() throws Exception {
+        final var result =
+                grammar.parse(Files.readString(Path.of("src/test/resources/graphml/graphA.graphml")));
+
+        assertTrue(result.isPresent());
+    }
+
+    @Test
+    public void graphmlGrammar_shouldParseLargeGraphmlFile() throws Exception {
+        final var result =
+                grammar.parse(Files.readString(Path.of("src/test/resources/graphml/air-routes-latest.graphml")));
+
+        assertTrue(result.isPresent());
+    }
+}

parsley-examples/src/test/resources/graphml/graphA.graphml

@@ -0,0 +1,74 @@
+<?xml version='1.0' ?>
+<!-- ******************************************************************************* -->
+<!-- Sample file containing selected air routes between selected airports.           -->
+<graphml xmlns='http://graphml.graphdrawing.org/xmlns'>
+<key id='type'    for='node' attr.name='type'    attr.type='string'></key>
+  <key id='code'    for='node' attr.name='code'    attr.type='string'></key>
+  <key id='icao'    for='node' attr.name='icao'    attr.type='string'></key>
+  <key id='desc'    for='node' attr.name='desc'    attr.type='string'></key>
+  <key id='region'  for='node' attr.name='region'  attr.type='string'></key>
+  <key id='runways' for='node' attr.name='runways' attr.type='int'></key>
+  <key id='longest' for='node' attr.name='longest' attr.type='int'></key>
+  <key id='elev'    for='node' attr.name='elev'    attr.type='int'></key>
+  <key id='country' for='node' attr.name='country' attr.type='string'></key>
+  <key id='city'    for='node' attr.name='city'    attr.type='string'></key>
+  <key id='lat'     for='node' attr.name='lat'     attr.type='double'></key>
+  <key id='lon'     for='node' attr.name='lon'     attr.type='double'></key>
+  <key id='author'  for='node' attr.name='author'  attr.type='string'></key>
+  <key id='date'    for='node' attr.name='date'    attr.type='string'></key>
+  <key id='dist'    for='edge' attr.name='dist'    attr.type='int'></key>
+  <key id='labelV'  for='node' attr.name='labelV'  attr.type='string'></key>
+  <key id='labelE'  for='edge' attr.name='labelE'  attr.type='string'></key>
+
+  <graph id='routes' edgedefault='directed'>
+    <node id='0'>
+      <data key='labelV'>version</data>
+      <data key='type'>version</data>
+      <data key='code'>0.84</data>
+      <data key='date'>2020-01-30 02:17:18 UTC</data>
+      <data key='author'>Kelvin R. Lawrence</data>
+      <data key='desc'>Air Routes Data - Version: 0.84 Generated: 2020-01-30 02:17:18 UTC; Graph created by Kelvin R. Lawrence; Please let me know of any errors you find in the graph.</data>
+    </node>
+      <node id='1'>
+        <data key='labelV'>airport</data>
+        <data key='type'>airport</data>
+        <data key='code'>ATL</data>
+        <data key='icao'>KATL</data>
+        <data key='city'>Atlanta</data>
+        <data key='desc'>Hartsfield - Jackson Atlanta International Airport</data>
+        <data key='region'>US-GA</data>
+        <data key='runways'>5</data>
+        <data key='longest'>12390</data>
+        <data key='elev'>1026</data>
+        <data key='country'>US</data>
+        <data key='lat'>33.6366996765137</data>
+        <data key='lon'>-84.4281005859375</data>
+      </node>
+      <node id='2'>
+        <data key='labelV'>airport</data>
+        <data key='type'>airport</data>
+        <data key='code'>ANC</data>
+        <data key='icao'>PANC</data>
+        <data key='city'>Anchorage</data>
+        <data key='desc'>Anchorage Ted Stevens</data>
+        <data key='region'>US-AK</data>
+        <data key='runways'>3</data>
+        <data key='longest'>12400</data>
+        <data key='elev'>151</data>
+        <data key='country'>US</data>
+        <data key='lat'>61.1744003295898</data>
+        <data key='lon'>-149.996002197266</data>
+      </node>
+
+
+  <edge id='3742' source='1' target='3'>
+    <data key='labelE'>route</data>
+    <data key='dist'>811</data>
+  </edge>
+  <edge id='3743' source='1' target='4'>
+    <data key='labelE'>route</data>
+    <data key='dist'>214</data>
+  </edge>
+
+  </graph>
+</graphml>

parsley-grammar/pom.xml

@@ -0,0 +1,82 @@
+<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/maven-v4_0_0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <artifactId>parsley-grammar</artifactId>
+  <packaging>jar</packaging>
+  <version>0.1.0-SNAPSHOT</version>
+
+  <name>parsley-grammar</name>
+
+  <parent>
+    <groupId>com.albertoventurini.parsley</groupId>
+    <artifactId>parsley</artifactId>
+    <version>0.1.0-SNAPSHOT</version>
+  </parent>
+
+  <url>https://github.com/albertoventurini/parsley</url>
+
+  <properties>
+    <antlr.version>4.7.1</antlr.version>
+    <junit.version>5.6.1</junit.version>
+    <maven-compiler-plugin.version>3.8.1</maven-compiler-plugin.version>
+    <maven-surefire-plugin.version>3.0.0-M5</maven-surefire-plugin.version>
+    <maven-jar-plugin.version>3.2.0</maven-jar-plugin.version>
+    <maven-shade.plugin.version>3.2.2</maven-shade.plugin.version>
+    <mainClass>com.albertoventurini.parsley.Main</mainClass>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter</artifactId>
+      <scope>test</scope>
+    </dependency>
+
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter-engine</artifactId>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+
+  <build>
+
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>${maven-compiler-plugin.version}</version>
+        <configuration>
+          <source>11</source>
+          <target>11</target>
+          <release>11</release>
+        </configuration>
+      </plugin>
+
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-surefire-plugin</artifactId>
+        <version>${maven-surefire-plugin.version}</version>
+        <configuration>
+          <argLine>--enable-preview</argLine>
+        </configuration>
+      </plugin>
+
+      <plugin>
+        <artifactId>maven-jar-plugin</artifactId>
+        <configuration>
+          <archive>
+            <manifest>
+              <addClasspath>true</addClasspath>
+              <mainClass>${mainClass}</mainClass>
+            </manifest>
+          </archive>
+        </configuration>
+      </plugin>
+    </plugins>
+
+  </build>
+
+</project>

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/Grammar.java

@@ -1,17 +1,17 @@
-package com.albertoventurini.parsley;
+package com.albertoventurini.parsley.grammar;
 
-import com.albertoventurini.parsley.rules.AnyCharacter;
+import com.albertoventurini.parsley.grammar.rules.AnyCharacter;
-import com.albertoventurini.parsley.rules.MatchCharacter;
+import com.albertoventurini.parsley.grammar.rules.MatchCharacter;
-import com.albertoventurini.parsley.rules.MatchString;
+import com.albertoventurini.parsley.grammar.rules.MatchString;
-import com.albertoventurini.parsley.rules.OneOf;
+import com.albertoventurini.parsley.grammar.rules.OneOf;
-import com.albertoventurini.parsley.rules.OneOrMore;
+import com.albertoventurini.parsley.grammar.rules.OneOrMore;
-import com.albertoventurini.parsley.rules.Rule;
+import com.albertoventurini.parsley.grammar.rules.Rule;
-import com.albertoventurini.parsley.rules.Sequence;
+import com.albertoventurini.parsley.grammar.rules.Sequence;
-import com.albertoventurini.parsley.rules.TakeWhileCharacter;
+import com.albertoventurini.parsley.grammar.rules.TakeWhileCharacter;
-import com.albertoventurini.parsley.rules.UntilString;
+import com.albertoventurini.parsley.grammar.rules.UntilString;
-import com.albertoventurini.parsley.rules.Wrapper;
+import com.albertoventurini.parsley.grammar.rules.Wrapper;
-import com.albertoventurini.parsley.rules.ZeroOrMore;
+import com.albertoventurini.parsley.grammar.rules.ZeroOrMore;
-import com.albertoventurini.parsley.rules.ZeroOrOne;
+import com.albertoventurini.parsley.grammar.rules.ZeroOrOne;
 
 import java.util.Optional;
 import java.util.function.Predicate;

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/GrammarContext.java

@@ -1,6 +1,6 @@
-package com.albertoventurini.parsley;
+package com.albertoventurini.parsley.grammar;
 
-import com.albertoventurini.parsley.rules.Rule;
+import com.albertoventurini.parsley.grammar.rules.Rule;
 
 public class GrammarContext extends ParseContext {
     private final Rule commentRule;

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/ParseContext.java

@@ -1,4 +1,4 @@
-package com.albertoventurini.parsley;
+package com.albertoventurini.parsley.grammar;
 
 import java.util.Arrays;
 

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/ParseException.java

@@ -1,4 +1,4 @@
-package com.albertoventurini.parsley;
+package com.albertoventurini.parsley.grammar;
 
 public class ParseException extends RuntimeException {
 

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/ParseTree.java

@@ -1,4 +1,4 @@
-package com.albertoventurini.parsley;
+package com.albertoventurini.parsley.grammar;
 
 import java.util.Collections;
 import java.util.List;

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/rules/AnyCharacter.java

@@ -1,7 +1,7 @@
-package com.albertoventurini.parsley.rules;
+package com.albertoventurini.parsley.grammar.rules;
 
-import com.albertoventurini.parsley.GrammarContext;
+import com.albertoventurini.parsley.grammar.GrammarContext;
-import com.albertoventurini.parsley.ParseTree;
+import com.albertoventurini.parsley.grammar.ParseTree;
 
 import java.util.Optional;
 

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/rules/MatchCharacter.java

@@ -1,7 +1,7 @@
-package com.albertoventurini.parsley.rules;
+package com.albertoventurini.parsley.grammar.rules;
 
-import com.albertoventurini.parsley.GrammarContext;
+import com.albertoventurini.parsley.grammar.GrammarContext;
-import com.albertoventurini.parsley.ParseTree;
+import com.albertoventurini.parsley.grammar.ParseTree;
 
 import java.util.Optional;
 

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/rules/MatchString.java

@@ -1,7 +1,7 @@
-package com.albertoventurini.parsley.rules;
+package com.albertoventurini.parsley.grammar.rules;
 
-import com.albertoventurini.parsley.GrammarContext;
+import com.albertoventurini.parsley.grammar.GrammarContext;
-import com.albertoventurini.parsley.ParseTree;
+import com.albertoventurini.parsley.grammar.ParseTree;
 
 import java.util.Optional;
 

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/rules/OneOf.java

@@ -1,7 +1,7 @@
-package com.albertoventurini.parsley.rules;
+package com.albertoventurini.parsley.grammar.rules;
 
-import com.albertoventurini.parsley.GrammarContext;
+import com.albertoventurini.parsley.grammar.GrammarContext;
-import com.albertoventurini.parsley.ParseTree;
+import com.albertoventurini.parsley.grammar.ParseTree;
 
 import java.util.Arrays;
 import java.util.Optional;

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/rules/OneOrMore.java

@@ -1,7 +1,7 @@
-package com.albertoventurini.parsley.rules;
+package com.albertoventurini.parsley.grammar.rules;
 
-import com.albertoventurini.parsley.GrammarContext;
+import com.albertoventurini.parsley.grammar.GrammarContext;
-import com.albertoventurini.parsley.ParseTree;
+import com.albertoventurini.parsley.grammar.ParseTree;
 
 import java.util.ArrayList;
 import java.util.List;

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/rules/Rule.java

@@ -1,7 +1,7 @@
-package com.albertoventurini.parsley.rules;
+package com.albertoventurini.parsley.grammar.rules;
 
-import com.albertoventurini.parsley.GrammarContext;
+import com.albertoventurini.parsley.grammar.GrammarContext;
-import com.albertoventurini.parsley.ParseTree;
+import com.albertoventurini.parsley.grammar.ParseTree;
 
 import java.util.Optional;
 

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/rules/Sequence.java

@@ -1,7 +1,7 @@
-package com.albertoventurini.parsley.rules;
+package com.albertoventurini.parsley.grammar.rules;
 
-import com.albertoventurini.parsley.GrammarContext;
+import com.albertoventurini.parsley.grammar.GrammarContext;
-import com.albertoventurini.parsley.ParseTree;
+import com.albertoventurini.parsley.grammar.ParseTree;
 
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -20,7 +20,7 @@ public final class Sequence extends Rule {
         final int start = ctx.getCursor();
         final List<ParseTree> children = new ArrayList<>(rules.length);
 
-        for (final Rule rule : rules) {
+        for (final com.albertoventurini.parsley.grammar.rules.Rule rule : rules) {
             if (!ctx.hasNext()) {
                 ctx.setCursor(start);
                 return Optional.empty();

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/rules/TakeWhileCharacter.java

@@ -1,7 +1,7 @@
-package com.albertoventurini.parsley.rules;
+package com.albertoventurini.parsley.grammar.rules;
 
-import com.albertoventurini.parsley.GrammarContext;
+import com.albertoventurini.parsley.grammar.GrammarContext;
-import com.albertoventurini.parsley.ParseTree;
+import com.albertoventurini.parsley.grammar.ParseTree;
 
 import java.util.Optional;
 import java.util.function.Predicate;

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/rules/UntilString.java

@@ -1,7 +1,7 @@
-package com.albertoventurini.parsley.rules;
+package com.albertoventurini.parsley.grammar.rules;
 
-import com.albertoventurini.parsley.GrammarContext;
+import com.albertoventurini.parsley.grammar.GrammarContext;
-import com.albertoventurini.parsley.ParseTree;
+import com.albertoventurini.parsley.grammar.ParseTree;
 
 import java.util.Arrays;
 import java.util.Optional;

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/rules/Wrapper.java

@@ -1,7 +1,7 @@
-package com.albertoventurini.parsley.rules;
+package com.albertoventurini.parsley.grammar.rules;
 
-import com.albertoventurini.parsley.GrammarContext;
+import com.albertoventurini.parsley.grammar.GrammarContext;
-import com.albertoventurini.parsley.ParseTree;
+import com.albertoventurini.parsley.grammar.ParseTree;
 
 import java.util.Optional;
 

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/rules/ZeroOrMore.java

@@ -1,7 +1,7 @@
-package com.albertoventurini.parsley.rules;
+package com.albertoventurini.parsley.grammar.rules;
 
-import com.albertoventurini.parsley.GrammarContext;
+import com.albertoventurini.parsley.grammar.GrammarContext;
-import com.albertoventurini.parsley.ParseTree;
+import com.albertoventurini.parsley.grammar.ParseTree;
 
 import java.util.ArrayList;
 import java.util.List;

parsley-grammar/src/main/java/com/albertoventurini/parsley/grammar/rules/ZeroOrOne.java

@@ -1,7 +1,7 @@
-package com.albertoventurini.parsley.rules;
+package com.albertoventurini.parsley.grammar.rules;
 
-import com.albertoventurini.parsley.GrammarContext;
+import com.albertoventurini.parsley.grammar.GrammarContext;
-import com.albertoventurini.parsley.ParseTree;
+import com.albertoventurini.parsley.grammar.ParseTree;
 
 import java.util.Optional;
 

parsley-grammar/src/test/java/com/albertoventurini/parsley/grammar/GrammarTest.java

@@ -0,0 +1,148 @@
+package com.albertoventurini.parsley.grammar;
+
+import com.albertoventurini.parsley.grammar.rules.Rule;
+import org.junit.jupiter.api.Test;
+
+import java.util.function.Function;
+
+import static com.albertoventurini.parsley.grammar.Grammar.character;
+import static com.albertoventurini.parsley.grammar.Grammar.oneOf;
+import static com.albertoventurini.parsley.grammar.Grammar.sequence;
+import static com.albertoventurini.parsley.grammar.Grammar.string;
+import static com.albertoventurini.parsley.grammar.Grammar.takeWhile;
+import static com.albertoventurini.parsley.grammar.Grammar.token;
+import static com.albertoventurini.parsley.grammar.Grammar.zeroOrMore;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class GrammarTest {
+
+    @Test
+    public void xmlTagWithoutAttributes() {
+        final Rule tag = sequence(
+                character('<'),
+                takeWhile(Character::isLetterOrDigit),
+                oneOf(string("/>"), character('>')));
+
+        final Grammar grammar = new Grammar(tag, null);
+
+        final var parseTree1 = grammar.parse("<tag1>");
+
+        assertTrue(parseTree1.isPresent());
+        assertEquals("tag1", parseTree1.get().child(0).getText());
+
+        final var parseTree2 = grammar.parse("<tag1 />");
+
+        assertTrue(parseTree2.isPresent());
+        assertEquals("tag1", parseTree2.get().child(0).getText());
+    }
+
+    @Test
+    public void xmlTagWithOptionalAttributes() {
+        final Rule token = takeWhile(Character::isLetterOrDigit);
+
+        final Rule attribute = sequence(token, character('='), token);
+
+        final Rule tag = sequence(
+                character('<'),
+                token,
+                zeroOrMore(attribute),
+                oneOf(string("/>"), character('>')));
+
+        final Grammar grammar = new Grammar(tag, null);
+
+        assertTrue(grammar.parse("<tag1>").isPresent());
+
+        final var parseTree1 = grammar.parse("<tag1 id=123>");
+
+        assertTrue(parseTree1.isPresent());
+        assertEquals("tag1", parseTree1.get().child(0).getText());
+        assertEquals("id", parseTree1.get().child(1) // get the zeroOrMore rule
+                .child(0) // get the first attribute
+                .child(0) // get the first element in the sequence rule
+                .getText()
+        );
+        assertEquals("123", parseTree1.get().child(1) // get the zeroOrMore rule
+                .child(0) // get the first attribute
+                .child(1) // get the second child in the sequence
+                .getText()
+        );
+
+        final var parseTree2 = grammar.parse("<tag1 hello=world something=else/>");
+
+        assertTrue(parseTree2.isPresent());
+        assertEquals("tag1", parseTree2.get().child(0).getText());
+
+        assertEquals("hello", parseTree2.get().child(1) // get the zeroOrMore rule
+                .child(0) // get the first attribute
+                .child(0) // get the first child in the sequence
+                .getText()
+        );
+        assertEquals("world", parseTree2.get().child(1) // get the zeroOrMore rule
+                .child(0) // get the first attribute
+                .child(1) // get the second child in the sequence
+                .getText()
+        );
+
+        assertEquals("something", parseTree2.get().child(1) // get the zeroOrMore rule
+                .child(1) // get the second attribute
+                .child(0) // get the first child in the sequence
+                .getText()
+        );
+        assertEquals("else", parseTree2.get().child(1) // get the zeroOrMore rule
+                .child(1) // get the second attribute
+                .child(1) // get the second child in the sequence
+                .getText()
+        );
+    }
+
+    @Test
+    public void xmlTagWithAttributeSurroundedByQuotes() {
+        final Rule attribute = sequence(
+                takeWhile(c -> c != '='),
+                character('='),
+                character('\''),
+                takeWhile(c -> c != '\''),
+                character('\''));
+
+        final Rule tag = sequence(
+                character('<'),
+                token(),
+                zeroOrMore(attribute),
+                oneOf(string("/>"), character('>')));
+
+        final Grammar grammar = new Grammar(tag, null);
+
+        assertTrue(grammar.parse("<graphml xmlns='http://graphml.graphdrawing.org/xmlns'>").isPresent());
+    }
+
+    @Test
+    public void elementWithoutContent() {
+        final Rule attribute = sequence(
+                takeWhile(c -> c != '=' && c != '>'),
+                character('='),
+                character('\''),
+                takeWhile(c -> c != '\''),
+                character('\''));
+
+        final Function<String, Rule> tagFunc = (s) -> sequence(
+                character('<'),
+                string(s),
+                zeroOrMore(attribute),
+                character('>'));
+
+        final Function<String, Rule> closingTagFunc = (s) -> sequence(
+                string("</"),
+                string(s),
+                string(">"));
+
+        final Rule key = sequence(
+                tagFunc.apply("key"),
+                closingTagFunc.apply("key"));
+
+        final Grammar grammar = new Grammar(key, null);
+
+        assertTrue(grammar.parse("<key id='type'    for='node' attr.name='type'    attr.type='string'></key>").isPresent());
+    }
+
+}

pom.xml

@@ -4,13 +4,18 @@
 
   <groupId>com.albertoventurini.parsley</groupId>
   <artifactId>parsley</artifactId>
-  <packaging>jar</packaging>
+  <packaging>pom</packaging>
   <version>0.1.0-SNAPSHOT</version>
 
-  <name>graphino</name>
+  <name>parsley</name>
 
   <url>https://github.com/albertoventurini/parsley</url>
 
+  <modules>
+    <module>parsley-grammar</module>
+    <module>parsley-examples</module>
+  </modules>
+
   <properties>
     <antlr.version>4.7.1</antlr.version>
     <junit.version>5.6.1</junit.version>