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.idea/.gitignore

+# Default ignored files
+/shelf/
+/workspace.xml
+# Datasource local storage ignored files
+/../../../../../../:\Users\Mostafa\Desktop\libSessionTwo\.idea/dataSources/
+/dataSources.local.xml
+# Editor-based HTTP Client requests
+/httpRequests/

.idea/misc.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_15" default="true" project-jdk-name="openjdk-15" project-jdk-type="JavaSDK">
+    <output url="file://$PROJECT_DIR$/out" />
+  </component>
+</project>
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.idea/modules.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/libSessionTwo.iml" filepath="$PROJECT_DIR$/libSessionTwo.iml" />
+    </modules>
+  </component>
+</project>
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libSessionTwo.iml

+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>
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src/Lab.java

+/**
+ * The Lab class represents a Lab class with all of students and
+ * referred information
+ * It holds the student details relevant in our context.
+ *
+ * @author SpNova
+ * @version 0.0
+ */
+
+public class Lab {
+    // stores a list of attendant students
+    private Student[] students;
+    // global variable for lab class average grade
+    private int avg;
+    // global variable for the day that lab class runs
+    private String day;
+    // global variable for capacity of lab class
+    private int capacity;
+    // global variable for attending number of students
+    private int currentSize;
+
+    /**
+     * constructor for lab class
+     *
+     * @param cap set capacity of lab class
+     * @param d   set day of lab class
+     */
+    public Lab(int cap, String d) {
+        capacity = cap;
+        day = d;
+        students = new Student[cap];
+    }
+
+    /**
+     * checks if lab class has capacity to enroll a student or not
+     * enrolls student to the lab class if there is enough capacity
+     * prints an error if lab is full
+     *
+     * @param std a student instance is called
+     */
+    public void enrollStudent(Student std) {
+
+        if (currentSize < capacity) {
+            students[currentSize] = std;
+            currentSize++;
+        } else {
+            System.out.println("Lab is full!!!");
+        }
+    }
+
+    /**
+     * prints all lab students personal data
+     * at last prints the average grade of all students in lab class
+     */
+    public void print() {
+        for (int i = 0; i < students.length; i++) {
+            System.out.println("FirstName: " + students[i].getFirstName() + "\tLastName: " + students[i].getLastName() +
+                    "\t\tID:" + students[i].getId() + "\t\tGrade:" + students[i].getGrade());
+        }
+        calculateAvg();
+        System.out.println("AVERAGE GRADE: " + getAvg());
+    }
+
+    /**
+     * returns a list of all attendant students
+     *
+     * @return students list
+     */
+    public Student[] getStudents() {
+        return students;
+    }
+
+    /**
+     * student field must be an array that contains all required data
+     *
+     * @param students set students list
+     */
+    public void setStudents(Student[] students) {
+        this.students = students;
+    }
+
+    /**
+     * get average grade of the class
+     *
+     * @return average field in INTEGER
+     */
+    public int getAvg() {
+        return avg;
+    }
+
+    /**
+     * calculates the average grade of class
+     */
+    public void calculateAvg() {
+        int sum = 0;
+        for (int i = 0; i < students.length; i++) {
+            sum = sum + students[i].getGrade();
+        }
+        avg = sum / students.length;
+    }
+
+    /**
+     * get the day that student attends the class
+     *
+     * @return day field
+     */
+    public String getDay() {
+        return day;
+    }
+
+    /**
+     * @param day set the day that student attends the class
+     */
+    public void setDay(String day) {
+        this.day = day;
+    }
+
+    /**
+     * get capacity of the class
+     *
+     * @return capacity field
+     */
+    public int getCapacity() {
+        return capacity;
+    }
+
+    /**
+     * @param capacity set capacity of the class
+     */
+    public void setCapacity(int capacity) {
+        this.capacity = capacity;
+    }
+
+    /**
+     * changes the first name of first student passed to this class
+     */
+    public void changeFirstStudentsFirstName() {
+        students[1].setFirstName("FOO");
+    }
+}
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src/Run.java

+public class Run {
+    public static void main(String[] args) {
+        Student std1 = new Student("Ehsan", "Edalat", "9031066");
+        Student std2 = new Student("Seyed", "Ahmadpanah", "9031806");
+        Student std3 = new Student("Ahmad", "Asadi", "9031054");
+        std1.print();
+        std1.setGrade(15);
+        std1.print();
+        std2.print();
+        std2.setGrade(11);
+        std2.print();
+        std3.print();
+        std3.setFirstName("HamidReza");
+        std3.print();
+        //Another Part Of HomeWork
+        System.out.println("-------------------------------------------------------");
+        Lab lab1 = new Lab(3, "Saturday Morning");
+        lab1.enrollStudent(std1);
+        lab1.enrollStudent(std2);
+        lab1.enrollStudent(std3);
+        lab1.print();
+        //"Think About It" Question
+        System.out.println("-------------------------------------------------------");
+        System.out.println("Sent Student Object Had The Value Of " + std1.getFirstName() + " For Fist Name");
+        lab1.changeFirstStudentsFirstName();
+        System.out.println("After Changing Method Now It Has Value Of " + std1.getFirstName() + " For Fist Name");
+        System.out.println("We See No Change In The Original Object! So Java Passes Objects By Their Value!");
+        //DEBUGGING Question
+        System.out.println("-------------------------------------------------------\n");
+        System.out.println("The Problem Is That Lab Average Is Not Calculated And Called Before Printing");
+
+    }
+}

src/Student.java

+/**
+ * The Student class represents a student in a student
+ * administration system.
+ * It holds the student details relevant in our context.
+ *
+ * @author Ehsan
+ * @version 0.0
+ */
+public class Student {
+    // the student’s first name
+    private String firstName;
+    // the student’s last name
+    private String lastName;
+    // the student ID
+    private String id;
+    //the grade
+    private int grade;
+
+    /**
+     * Create a new student with a given name and ID number.
+     *
+     * @param fName first name of student
+     * @param lname last name of student
+     * @param sID   student ID
+     */
+    public Student(String fName, String lname, String sID) {
+        firstName = fName;
+        lastName = lname;
+        id = sID;
+        grade = 0;
+    }
+
+    /**
+     * get the first name of student
+     *
+     * @return firstName field
+     */
+    public String getFirstName() {
+        return firstName;
+    }
+
+    /**
+     * @param firstName set first name of a student
+     */
+    public void setFirstName(String firstName) {
+        this.firstName = firstName;
+    }
+
+    /**
+     * get the first name of student
+     *
+     * @return lastName field
+     */
+    public String getLastName() {
+        return lastName;
+    }
+
+    /**
+     * @param lastName set first name of a student
+     */
+    public void setLastName(String lastName) {
+        this.lastName = lastName;
+    }
+
+    /**
+     * get the first name of student
+     *
+     * @return id field
+     */
+    public String getId() {
+        return id;
+    }
+
+    /**
+     * @param id set first name of a student
+     */
+    public void setId(String id) {
+        this.id = id;
+    }
+
+    /**
+     * get the first name of student
+     *
+     * @return grade field
+     */
+    public int getGrade() {
+        return grade;
+    }
+
+    /**
+     * @param grade set first name of a student
+     */
+    public void setGrade(int grade) {
+        this.grade = grade;
+    }
+
+    /**
+     * Print the student’s last name and ID number to the
+     * output terminal.
+     */
+    public void print() {
+        System.out.println(lastName + ", student ID: "
+                + id + ", grade: " + grade);
+    }
+}
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