java array list

src/java/.gitignore

@@ -0,0 +1,23 @@
+# Compiled class file
+*.class
+
+# Log file
+*.log
+
+# BlueJ files
+*.ctxt
+
+# Mobile Tools for Java (J2ME)
+.mtj.tmp/
+
+# Package Files #
+*.jar
+*.war
+*.nar
+*.ear
+*.zip
+*.tar.gz
+*.rar
+
+# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
+hs_err_pid*

src/java/base/CommandLineArgs/CommandLineArgs.java

@@ -2,13 +2,13 @@
  * Author: fasion
  * Created time: 2019-07-20 12:20:13
  * Last Modified by: fasion
- * Last Modified time: 2019-07-20 12:22:58
+ * Last Modified time: 2019-07-22 16:03:24
  */
 
 public class CommandLineArgs {
-    public static void main(String args[]) {
-        for (int i=0; i<args.length; i++) {
-            System.out.printf("Args %d: `%s`\n", i, args[i]);
-        }
-    }
+	public static void main(String args[]) {
+		for (int i=0; i<args.length; i++) {
+			System.out.printf("Args %d: `%s`\n", i, args[i]);
+		}
+	}
 }

src/java/base/CommandLineArgs/Makefile

@@ -0,0 +1,18 @@
+# FileName:   Makefile
+# Author:     Fasion Chan
+# @contact:   fasionchan@gmail.com
+# @version:   $Id$
+#
+# Description:
+#
+# Changelog:
+#
+
+build:
+	javac CommandLineArgs.java
+
+run:
+	java CommandLineArgs
+
+clean:
+	rm -rf *.class

src/java/base/HelloWorld/HelloWorld.java

@@ -2,11 +2,11 @@
  * Author: fasion
  * Created time: 2019-07-20 12:18:01
  * Last Modified by: fasion
- * Last Modified time: 2019-07-20 12:18:40
+ * Last Modified time: 2019-07-22 15:54:06
  */
 
 public class HelloWorld {
-    public static void main(String args[]) {
-        System.out.println("Hello, world!");
-    }
+	public static void main(String args[]) {
+		System.out.println("Hello, world!");
+	}
 }

src/java/base/HelloWorld/Makefile

@@ -0,0 +1,13 @@
+# Author: fasion
+# Created time: 2019-07-20 14:56:34
+# Last Modified by: fasion
+# Last Modified time: 2019-07-22 09:27:55
+
+build:
+	javac HelloWorld.java
+
+run:
+	java HelloWorld
+
+clean:
+	rm -rf *.class

src/java/base/ObjectOriented/encapsulation/Counter/Counter.java

@@ -0,0 +1,43 @@
+/*
+ * Author: fasion
+ * Created time: 2019-07-20 15:38:55
+ * Last Modified by: fasion
+ * Last Modified time: 2019-07-22 16:03:33
+ */
+
+public class Counter {
+	int count;
+
+	public Counter() {
+		count = 0;
+	}
+
+	public void add() {
+		count += 1;
+	}
+
+	public void reset() {
+		count = 0;
+	}
+
+	public int get() {
+		return count;
+	}
+
+	public static void main(String args[]) {
+		Counter counter = new Counter();
+		System.out.printf("Initial: %d\n", counter.get());
+
+		counter.add();
+		System.out.printf("After first add: %d\n", counter.get());
+
+		counter.add();
+		System.out.printf("After second add: %d\n", counter.get());
+
+		counter.reset();
+		System.out.printf("After reset: %d\n", counter.get());
+
+		counter.add();
+		System.out.printf("After another add: %d\n", counter.get());
+	}
+}

src/java/base/ObjectOriented/encapsulation/Counter/Makefile

@@ -0,0 +1,13 @@
+# Author: fasion
+# Created time: 2019-07-21 09:25:54
+# Last Modified by: fasion
+# Last Modified time: 2019-07-22 09:27:32
+
+build:
+	javac Counter.java
+
+run:
+	java Counter
+
+clean:
+	rm -rf *.class

src/java/base/recursion/Fibonacci/Fibonacci.java

@@ -2,19 +2,19 @@
  * Author: fasion
  * Created time: 2019-07-20 12:02:52
  * Last Modified by: fasion
- * Last Modified time: 2019-07-20 12:16:29
+ * Last Modified time: 2019-07-22 16:03:47
  */
 
 public class Fibonacci {
-    public static int fibonacci(int n) {
-        if (n==1 || n==2) {
-            return 1;
-        }
-        return Fibonacci.fibonacci(n-1) + Fibonacci.fibonacci(n-2);
-    }
+	public static int fibonacci(int n) {
+		if (n==1 || n==2) {
+			return 1;
+		}
+		return Fibonacci.fibonacci(n-1) + Fibonacci.fibonacci(n-2);
+	}
 
-    public static void main(String[] args) {
-        int n = Integer.parseInt(args[0]);
-        System.out.println(Fibonacci.fibonacci(n));
-    }
+	public static void main(String[] args) {
+		int n = Integer.parseInt(args[0]);
+		System.out.println(Fibonacci.fibonacci(n));
+	}
 }

src/java/base/recursion/Fibonacci/Makefile

@@ -0,0 +1,18 @@
+# FileName:   Makefile
+# Author:     Fasion Chan
+# @contact:   fasionchan@gmail.com
+# @version:   $Id$
+#
+# Description:
+#
+# Changelog:
+#
+
+build:
+	javac Fibonacci.java
+
+run:
+	java Fibonacci
+
+clean:
+	rm -rf *.class

src/java/linear/ArrayList/ArrayList.java

@@ -0,0 +1,170 @@
+/*
+ * Author: fasion
+ * Created time: 2019-07-20 16:16:06
+ * Last Modified by: fasion
+ * Last Modified time: 2019-07-22 13:59:07
+ */
+
+public class ArrayList<AnyType> implements Iterable<AnyType> {
+	private static final int DEFAULT_CAPACITY = 10;
+
+	private int listSize;
+	private AnyType[] listItems;
+
+	public ArrayList() {
+		listItems = (AnyType[]) new Object[DEFAULT_CAPACITY];
+		listSize = 0;
+	}
+
+	public int size() {
+		return listSize;
+	}
+
+	public int capacity() {
+		return listItems.length;
+	}
+
+	public boolean isEmpty() {
+		return size() == 0;
+	}
+
+	public boolean isFull() {
+		return size() == capacity();
+	}
+
+	public AnyType get(int idx) {
+		if (idx < 0 || idx >= size()) {
+			throw new ArrayIndexOutOfBoundsException();
+		}
+		return listItems[idx];
+	}
+
+	public AnyType set(int idx, AnyType newVal) {
+		if (idx < 0 || idx >= size()) {
+			throw new ArrayIndexOutOfBoundsException();
+		}
+
+		AnyType old = listItems[idx];
+		listItems[idx] = newVal;
+
+		return old;
+	}
+
+	public void ensureCapacity(int newCapacity) {
+		if (newCapacity <= capacity()) {
+			return;
+		}
+
+		AnyType [] oldItems = listItems;
+
+		listItems = (AnyType []) new Object[newCapacity];
+		for (int i = 0; i < size(); i++) {
+			listItems[i] = oldItems[i];
+		}
+	}
+
+	public void add(int idx, AnyType x) {
+		if (size() == capacity()) {
+			ensureCapacity(capacity() * 2);
+		}
+
+		for (int i = size(); i > idx; i--) {
+			listItems[i] = listItems[i-1];
+		}
+
+		listItems[idx] = x;
+		listSize++;
+	}
+
+	public void add(AnyType x) {
+		add(size(), x);
+	}
+
+	public AnyType remove(int idx) {
+		if (idx < 0 || idx >= size()) {
+			throw new ArrayIndexOutOfBoundsException();
+		}
+
+		AnyType value = listItems[idx];
+
+		for (int i = idx; i < size() - 1; i++) {
+			listItems[i] = listItems[i+1];
+		}
+
+		listSize--;
+
+		return value;
+	}
+
+	public void print(String hint) {
+		System.out.printf("%s[", hint);
+
+		for (int i = 0; i < listSize; i++) {
+			System.out.printf("%s ", listItems[i]);
+		}
+
+		System.out.printf("]\n");
+	}
+
+	private class ArrayListIterator implements java.util.Iterator<AnyType> {
+		private int current = 0;
+
+		public boolean hasNext() {
+			return current < size();
+		}
+
+		public AnyType next() {
+			if (!hasNext()) {
+				throw new java.util.NoSuchElementException();
+			}
+			return listItems[current++];
+		}
+
+		public void remove() {
+			ArrayList.this.remove(--current);
+		}
+	}
+
+	public java.util.Iterator<AnyType> iterator() {
+		return new ArrayListIterator();
+	}
+
+	public static void main(String args[]) {
+		ArrayList<Integer> list = new ArrayList<Integer>();
+		list.print("After init: ");
+		System.out.println();
+
+		list.add(1);
+		list.add(2);
+		list.add(3);
+
+		list.print("After add 1, 2, 3: ");
+		System.out.printf("#1 is: %d\n", list.get(1));
+		System.out.println();
+
+		list.add(0, -1);
+		list.print("After insert -1: ");
+		System.out.println();
+
+		list.remove(1);
+		list.print("After remove #1: ");
+		System.out.println();
+
+		list.add(4);
+		list.print("After append 4: ");
+		System.out.println();
+
+		for (int i = 5; i < 20; i++) {
+			list.add(i);
+		}
+
+		list.print("Finally: ");
+		System.out.println();
+
+		System.out.println("iterate over list");
+		java.util.Iterator<Integer> it = list.iterator();
+		while (it.hasNext()) {
+			System.out.println(it.next());
+		}
+	}
+}

src/java/linear/ArrayList/Makefile

@@ -0,0 +1,13 @@
+# Author: fasion
+# Created time: 2019-07-20 14:56:34
+# Last Modified by: fasion
+# Last Modified time: 2019-07-22 13:28:43
+
+build:
+	javac ArrayList.java
+
+run:
+	java ArrayList
+
+clean:
+	rm -rf *.class