Added javaGsonObjectsJava10

contributions/javaGsonObjectsJava10/.gitignore

@@ -0,0 +1,9 @@
+*.class
+.gradle/
+.settings/
+.classpath
+.project
+bin/
+build/
+libs/
+outputs/

contributions/javaGsonObjectsJava10/README.md

@@ -0,0 +1,128 @@
+This is an implementation of the 101companies System.
+
+== Headline ==
+Working on [[Language:JSON|]] with Google [[Technology:Gson|Gson API]], mapping Json to a direct object representation
+
+== Characteristics ==
+This contribution modernizes the [[Contribution:javaGsonObjects]] (which is a simple company structure, displaying the serialization process using [[Language:JSON]] for storing the company structure and Gson API for parsing, unparsing and manipulating it the JSON.), by utilizing new features, introduced up to Java10, such as [[Concept:Lambda abstraction]] and [[Concept:Streaming]].
+
+== Illustration ==
+To Parse a JSON File you can either use "parseFromFile(String path)" or "parseFromFile(File file)"
+The former is only a wrapper method for the latter, so we'll be taking a look at the "parseFromFile(File file)" method.
+<syntaxhighlight lang="java">
+	/**
+	 * Method to parse a JSON file to a Company
+	 * 
+	 * @param file Path for JSON file
+	 * @return a Company representing the JSON file
+	 * @throws IOException
+	 * @throws FileNotFoundException
+	 */
+	public static Company parseFromFile(File file) throws FileNotFoundException, IOException {
+		Gson gson = new Gson();
+		try (JsonReader read = new JsonReader(new FileReader(file))) {
+			return gson.fromJson(read, Company.class);
+		}
+	}
+</syntaxhighlight>
+Given a JSON file, the method will create a Gson object and attempt to read the file using a JsonReader.
+Should the file not be found, the method will throw a FileNotFoundException.
+Were there problems reading the File, then an IOException will be thrown.
+The method will proceed to the last instuction if the file was read without any problems.
+<code>gson.fromJson(read, Company.class);</code>
+Here, the "fromJson" method of the gson object, is parsing the read JSON data into an object of type Company.
+Alternatively, you can call the "parse(String jsonString)" method directly, if you have already read the JSON file into a string.
+<syntaxhighlight lang="java">
+	/**
+	 * Method to parse a JSON String to a Company
+	 * 
+	 * @param jsonString String containing JSON
+	 * @return a Company representing the JSON from the jsonString
+	 */
+	public static Company parse(String jsonString) {
+		Gson gson = new Gson();
+		return gson.fromJson(jsonString, Company.class);
+	}
+</syntaxhighlight>
+
+The Unparsing methods are very similar to the parsing ones.
+Like in the Parsing class, we defined a wrapper function for the parameter path.
+The "unparseToFile(Company company, File file)" method looks as follows:
+<syntaxhighlight lang="java">
+	/**
+	 * Method to parse a Company to a JSON File
+	 * 
+	 * @param company Company to be parsed to a JSON File
+	 * @param file    Destination File for the JSON File
+	 * @throws IOException
+	 */
+	public static void unparseToFile(Company company, File file) throws IOException {
+		GsonBuilder builder = new GsonBuilder();
+		builder.setPrettyPrinting();
+		Gson gson = builder.create();
+		try (FileWriter writer = new FileWriter(file)) {
+			gson.toJson(company, writer);
+		}
+	}
+</syntaxhighlight>
+Let us take a closer look into it's inner workings.
+The line...
+<code> GsonBuilder builder = new GsonBuilder();</code>
+...leaves us with a GsonBuilder object, which will serve the purpose of creating the gson object we'll be using to create and write the JSON file with.
+We then proceed in creating a FileWriter object via a try-with-resources statement.
+<syntaxhighlight lang="java">
+    try (FileWriter writer = new FileWriter(file)) {
+        gson.toJson(c, writer);
+    }
+</syntaxhighlight>
+The FileWriter is then used by the gson object to write the JSON representation of the company into the file given by the user.
+
+The string representation of a company object in the JSON format can be obtained directly, without being written to a file, by the "unparse(Company company)" method.
+<syntaxhighlight lang="java">
+	/**
+	 * Method to parse a Company to a JSON String
+	 * 
+	 * @param company Company to be parsed to a JSON File
+	 * @return a String representing the JSON File of the company
+	 */
+	public static String unparse(Company company) {
+		GsonBuilder builder = new GsonBuilder();
+		builder.setPrettyPrinting();
+		Gson gson = builder.create();
+		return gson.toJson(company);
+	}
+</syntaxhighlight>
+
+== Relationships ==
+[[Contribution:javaGsonObjects] is the base for this contribution.
+[[Contribution:javaGson]] is using the same Api and Features with a different JSON mapping.
+
+== Architecture ==
+The contribution follows a standardized structure:
+* inputs contains input files for tests
+* src/main/java contains the following packages:
+** org.softlang.company.model for implementations of [[Feature:Hierarchical company]].
+** org.softlang.company.features for implementations of [[Namespace:Feature]].
+* src/test/java contains the following packages:
+** org.softlang.company.tests for [[Technology:JUnit]] test cases for [[Namespace:Feature]]s.
+
+== Usage ==
+This contribution uses [[Technology:Gradle]] for building. [[Technology:Eclipse]] is supported.
+See: https://github.com/101companies/101simplejava/blob/master/README.md
+
+== Metadata ==
+* [[developedBy::Contributor:mpaul138]]
+* [[implements::Feature:Hierarchical company]]
+* [[implements::Feature:Unparsing]]
+* [[implements::Feature:Parsing]]
+* [[implements::Feature:Total]]
+* [[implements::Feature:Cut]]
+* [[implements::Feature:Mapping]]
+* [[implements::Feature:Serialization]]
+* [[memberOf::Theme:Java mapping]]
+* [[uses::Language:JSON]]
+* [[uses::Language:Plain Text]]
+* [[uses::Language:Java]]
+* [[uses::Technology:Gson]]
+* [[uses::Technology:JUnit]]
+* [[uses::Technology:Gradle]]

contributions/javaGsonObjectsJava10/build.gradle

@@ -0,0 +1,26 @@
+apply plugin: 'java'
+apply plugin: 'eclipse'
+
+group = 'org.softlang.company'
+sourceCompatibility = JavaVersion.VERSION_1_10
+targetCompatibility = JavaVersion.VERSION_1_10
+version = '1.0.0'
+
+// Implementation specifics
+// This implementation uses JUnit for testing
+dependencies {
+	compile group: 'com.google.code.gson', name: 'gson', version: '2.8.5'
+    testCompile group: 'org.junit.jupiter', name: 'junit-jupiter-api', version: '5.3.1'
+    testCompile group: 'org.junit.jupiter', name: 'junit-jupiter-engine', version: '5.3.1'
+}
+// Additional cleanup for outputs
+clean {
+	dependsOn cleanEclipse
+	doFirst {
+		delete 'outputs'
+	}
+}
+// JUnit 5 support
+test {
+    useJUnitPlatform()
+}

contributions/javaGsonObjectsJava10/inputs/sampleCompany.json

@@ -0,0 +1,41 @@
+{
+  "name": "Acme Corporation",
+  "departments": [
+    {
+      "name": "Research",
+      "manager": {
+        "name": "Fred",
+        "salary": 88888.0
+      }
+    },
+    {
+      "name": "Development",
+      "manager": {
+        "name": "Marie",
+        "salary": 77777.0
+      },
+      "departments": [
+        {
+          "name": "Dev1",
+          "manager": {
+            "name": "Bob",
+            "salary": 77776.0
+          }
+        },
+        {
+          "name": "Dev2",
+          "manager": {
+            "name": "Alice",
+            "salary": 77775.0
+          },
+          "employees": [
+            {
+              "name": "Ralf",
+              "salary": 4711.0
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}

contributions/javaGsonObjectsJava10/src/main/java/org/softlang/company/features/Cut.java

@@ -0,0 +1,42 @@
+package org.softlang.company.features;
+
+import java.util.Optional;
+
+import org.softlang.company.model.Company;
+import org.softlang.company.model.Department;
+import org.softlang.company.model.Employee;
+
+public class Cut {
+
+	/**
+	 * Method to cut salaries in half
+	 * 
+	 * @param company Company to cut salaries from
+	 */
+	public static void cut(Company company) {
+		Optional.ofNullable(company).map(Company::getDepartments)
+				.ifPresent(departments -> departments.forEach(Cut::cut));
+	}
+
+	/**
+	 * Helper method for cut
+	 * 
+	 * @param department Department to cut salaries from
+	 */
+	private static void cut(Department department) {
+		Optional.ofNullable(department.getManager()).ifPresent(Cut::cut);
+
+		Optional.ofNullable(department.getEmployees()).ifPresent(employees -> employees.forEach(Cut::cut));
+
+		Optional.ofNullable(department.getDepartments()).ifPresent(departments -> departments.forEach(Cut::cut));
+	}
+
+	/**
+	 * Helper method for cut
+	 * 
+	 * @param employee Employee to cut salary from
+	 */
+	private static void cut(Employee employee) {
+		employee.setSalary(employee.getSalary() / 2);
+	}
+}

contributions/javaGsonObjectsJava10/src/main/java/org/softlang/company/features/Parsing.java

@@ -0,0 +1,52 @@
+package org.softlang.company.features;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileReader;
+import java.io.IOException;
+
+import org.softlang.company.model.Company;
+
+import com.google.gson.Gson;
+import com.google.gson.stream.JsonReader;
+
+public class Parsing {
+
+	/**
+	 * Method to parse a JSON file to a Company
+	 * 
+	 * @param path Path to the JSON file
+	 * @return a Company representing the JSON file
+	 * @throws IOException
+	 * @throws FileNotFoundException
+	 */
+	public static Company parseFromFile(String path) throws FileNotFoundException, IOException {
+		return parseFromFile(new File(path));
+	}
+
+	/**
+	 * Method to parse a JSON file to a Company
+	 * 
+	 * @param file Path for JSON file
+	 * @return a Company representing the JSON file
+	 * @throws IOException
+	 * @throws FileNotFoundException
+	 */
+	public static Company parseFromFile(File file) throws FileNotFoundException, IOException {
+		Gson gson = new Gson();
+		try (JsonReader read = new JsonReader(new FileReader(file))) {
+			return gson.fromJson(read, Company.class);
+		}
+	}
+
+	/**
+	 * Method to parse a JSON String to a Company
+	 * 
+	 * @param jsonString String containing JSON
+	 * @return a Company representing the JSON from the jsonString
+	 */
+	public static Company parse(String jsonString) {
+		Gson gson = new Gson();
+		return gson.fromJson(jsonString, Company.class);
+	}
+}

contributions/javaGsonObjectsJava10/src/main/java/org/softlang/company/features/Total.java

@@ -0,0 +1,37 @@
+package org.softlang.company.features;
+
+import java.util.Optional;
+
+import org.softlang.company.model.Company;
+import org.softlang.company.model.Department;
+import org.softlang.company.model.Employee;
+
+public class Total {
+
+	/**
+	 * Method to get the total of all salaries
+	 * 
+	 * @param company Company to compute total for
+	 * @return total of Company company
+	 */
+	public static double total(Company company) {
+		return Optional.ofNullable(company).map(Company::getDepartments)
+				.map(departments -> departments.stream().mapToDouble(Total::total).sum()).orElse(0.0);
+	}
+
+	/**
+	 * Helper Method to get the total of all salaries in a Department
+	 * 
+	 * @param department Department to compute the total for
+	 * @return total of all salaries in Department department
+	 */
+	private static double total(Department d) {
+		double sum = Optional.ofNullable(d.getManager()).map(Employee::getSalary).orElse(0.0);
+
+		sum += Optional.ofNullable(d.getEmployees())
+				.map(employees -> employees.stream().mapToDouble(Employee::getSalary).sum()).orElse(0.0);
+
+		return sum + Optional.ofNullable(d.getDepartments())
+				.map(departments -> departments.stream().mapToDouble(Total::total).sum()).orElse(0.0);
+	}
+}

contributions/javaGsonObjectsJava10/src/main/java/org/softlang/company/features/Unparsing.java

@@ -0,0 +1,54 @@
+package org.softlang.company.features;
+
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+
+import org.softlang.company.model.Company;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+
+public class Unparsing {
+
+	/**
+	 * Method to parse a Company to a JSON File
+	 * 
+	 * @param company Company to be parsed to a JSON File
+	 * @param path    Destination Path for the JSON File
+	 * @throws IOException
+	 */
+	public static void unparseToFile(Company comapny, String path) throws IOException {
+		unparseToFile(comapny, new File(path));
+	}
+
+	/**
+	 * Method to parse a Company to a JSON File
+	 * 
+	 * @param company Company to be parsed to a JSON File
+	 * @param file    Destination File for the JSON File
+	 * @throws IOException
+	 */
+	public static void unparseToFile(Company company, File file) throws IOException {
+		GsonBuilder builder = new GsonBuilder();
+		builder.setPrettyPrinting();
+		Gson gson = builder.create();
+		try (FileWriter writer = new FileWriter(file)) {
+			gson.toJson(company, writer);
+		}
+	}
+
+	/**
+	 * Method to parse a Company to a JSON String
+	 * 
+	 * @param company Company to be parsed to a JSON File
+	 * @return a String representing the JSON File of the company
+	 */
+	public static String unparse(Company company) {
+		GsonBuilder builder = new GsonBuilder();
+		builder.setPrettyPrinting();
+		Gson gson = builder.create();
+		return gson.toJson(company);
+	}
+
+}