Core Java

Author: sathishmepco

Collections/src/com/cdac/collections/bean/Student.java

@@ -1,6 +1,6 @@
 package com.cdac.collections.bean;
 
-public class Student implements Comparable<Student>{
+public class Student implements Comparable<Student>,Cloneable{
 
 	private int rollNo;
 	private String name;
@@ -53,4 +53,9 @@ public int compareTo(Student o) {
 		//DECREASING ORDER BY ROLL NO
 //		return o.rollNo - this.rollNo ;
 	}
+	
+	@Override
+	public Object clone() throws CloneNotSupportedException {
+		return super.clone();
+	}
 }

Collections/src/com/cdac/collections/collectionsutils/CollectionsDemo.java

@@ -15,25 +15,41 @@ public static void main(String[] args) {
 		list.add("One");
 		list.add("Two");
 		list.add("One");
+		System.out.println("Initial List");
+		System.out.println(list);
 
 		Set<String> set = new HashSet<>();
 		set.add("Three");
 		set.add("Four");
 		set.add("One");
-		
+		System.out.println("Initial Set");
 		System.out.println(set);
+		
+		//Adding all list elements to Set Collection
 		set.addAll(list);
+		System.out.println("Adding list to set collection");
 		System.out.println(set);
 
+		//Adding array values to List Collection
+		String strArray[] = {"ABC","acb"};
+		Collections.addAll(list, strArray);
+		System.out.println("Adding Array values to List collection ");
+		System.out.println(list);
+
+		//sorting the List Collection
 		Collections.sort(list);
-		System.out.println("Sort : "+list);
+		System.out.println("Sorting the List : ");
+		System.out.println(list);
+		
+		//sorting the list with comparator - reverse order
 		Collections.sort(list, Collections.reverseOrder());
-		System.out.println("Reverse Order : "+list);
+		System.out.println("Reverse Order : ");
+		System.out.println(list);
 
 		String max = Collections.max(list);
-		System.out.println("Max : "+max);
+		System.out.println("Max Element in the List : "+max);
 		String min = Collections.min(list);
-		System.out.println("Min : "+min);
+		System.out.println("Min Element in the List : "+min);
 
 		List<Integer> iList = new ArrayList<>();
 		iList.add(10);
@@ -69,5 +85,7 @@ public static void main(String[] args) {
 
 		Map<Integer, String> map = new HashMap<>();
 		map = Collections.synchronizedMap(map);
+		
+		
 	}
-}
+}

Collections/src/com/cdac/collections/threadsafe/EmployeeRunnable.java

@@ -0,0 +1,18 @@
+package com.cdac.collections.threadsafe;
+
+import java.util.ArrayList;
+
+public class EmployeeRunnable implements Runnable{
+
+	ArrayList<String> names;
+	
+	public EmployeeRunnable(ArrayList<String> list) {
+		this.names = list;
+	}
+	
+	@Override
+	public void run() {
+		for(int i=0;i<100;i++)
+			names.add("Employee :: "+i);
+	}
+}

Collections/src/com/cdac/collections/threadsafe/MainProgram.java

@@ -0,0 +1,22 @@
+package com.cdac.collections.threadsafe;
+
+import java.util.ArrayList;
+
+import com.cdac.collections.bean.Student;
+
+public class MainProgram {
+	public static void main(String[] args) throws CloneNotSupportedException {
+		ArrayList<String> list = new ArrayList<>();
+		EmployeeRunnable employeeRunnable = new EmployeeRunnable(list);
+		StudentRunnable studentRunnable = new StudentRunnable(list);
+		
+		Thread t1 = new Thread(employeeRunnable);
+		Thread t2 = new Thread(studentRunnable);
+		
+		t1.start();
+		t2.start();
+		
+				
+				
+	}
+}

Collections/src/com/cdac/collections/threadsafe/ShallowCopy_DeepCopy.java

@@ -0,0 +1,19 @@
+package com.cdac.collections.threadsafe;
+
+import com.cdac.collections.bean.Student;
+
+public class ShallowCopy_DeepCopy {
+	public static void main(String[] args) throws CloneNotSupportedException {
+		//Shallow copy
+		Student s1 = new Student(101, "Atul", 80);
+		Student s2 = s1;
+		s2.setMarks(85);
+		System.out.println("Shallow Copy");
+		System.out.println(s2.getMarks()+" "+s1.getMarks());
+		
+		Student s3 = (Student) s1.clone();
+		s3.setMarks(90);
+		System.out.println("Deep Copy");
+		System.out.println(s3.getMarks() +" "+s1.getMarks());
+	}
+}

Collections/src/com/cdac/collections/threadsafe/StudentRunnable.java

@@ -0,0 +1,18 @@
+package com.cdac.collections.threadsafe;
+
+import java.util.ArrayList;
+
+public class StudentRunnable implements Runnable{
+
+	ArrayList<String> names;
+	
+	public StudentRunnable(ArrayList<String> list) {
+		this.names = list;
+	}
+	@Override
+	public void run() {
+		for(int i=100;i<200;i++)
+			names.add("Student :: "+i);
+	}
+
+}

FileIO/src/com/cdac/fileio/bytestream/CharacterStream.java

@@ -4,11 +4,12 @@
 import java.io.FileReader;
 import java.io.FileWriter;
 import java.io.IOException;
+import java.nio.CharBuffer;
 
 public class CharacterStream {
 
 	public static void main(String[] args) throws IOException {
-		String content = "Hi Good morning!";
+		String content = "Hi -1 Good morning!";
 		writeToFile(content);
 		readFromFile();
 	}
@@ -35,11 +36,14 @@ public static void readFromFile(){
 		FileReader fileReader = null;
 		try {
 			fileReader = new FileReader(filePath);
-			int i;
+			/*int i;
 			while ( (i = fileReader.read()) != -1){
 				char ch = (char) i;
 				System.out.print(ch);
-			}
+			}*/
+			CharBuffer buffer = null;
+			fileReader.read(buffer);
+			System.out.println(buffer.toString());
 		} catch (FileNotFoundException e) {
 			e.printStackTrace();
 		} catch (IOException e) {

FileIO/src/com/cdac/fileio/bytestream/TestErroStream.java

@@ -0,0 +1,20 @@
+package com.cdac.fileio.bytestream;
+
+import java.io.FileReader;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.Reader;
+
+public class TestErroStream {
+	public static void main(String[] args) throws IOException {
+	
+		int b = System.in.read();
+		
+		for(int i=0;i<5;i++){
+			System.out.println("Hello");
+			System.out.flush(); 
+			System.err.println("Error");
+		}
+	}
+}