Best Data Container

Java

by techbard 2016. 7. 8. 21:59

# Animal.java

public class Animal {

private String name;

public Animal() {
}

public Animal(String name) {
this.name = name;
}

public String getName() {
return name;
}

@Override
public String toString() {
return String.format("%s, %s\n", getClass(), this.name);
}

@Override
public boolean equals(Object obj) {
if (obj == null) {
return false;
}

if (!(obj instanceof Animal)) {
return false;
}

return (this.getName().equals(((Animal)obj).getName()));
}
}

# BestDataContainer.java

import java.util.NoSuchElementException;

public class BestDataContainer<T> {

private Object[] data;
public int countItems;

public BestDataContainer() {
this(10);
}

public BestDataContainer(int capacity) {
data = new Object[capacity];
countItems = 0;
}

public int size() {
return countItems;
}

public boolean add(T item) {
if (item == null) {
return false;
}

if (countItems == data.length) {
return false;
}

int itemIndex = findItem(item);
if (itemIndex > 0) {
return false;
}

data[countItems++] = item;
return true;
}

public boolean remove(int index) {
validateIndex(index);
int i = index;
int j = i + 1;

while (j < countItems) {
data[j - 1] = data[j];
j++;
}
countItems--;
return true;
}

public boolean remove(T item) {
if (item == null) {
return false;

}

int index = findItem(item);
if (index < 0) {
return false;
}

return remove(index);
}

public int findItem(T item) {
for (int i = 0; i < countItems; i++) {
if (data[i].equals(item)) {
return i;
}
}

return -1;
}

public T get(int index) {
validateIndex(index);
return (T) data[index];
}

private void validateIndex(int index) {
if (index < 0 && index >= countItems) {
throw new NoSuchElementException("Invalid Index");
}
}

@Override
public String toString() {
StringBuilder sb = new StringBuilder();

for (int i = 0; i < countItems; i++) {
sb.append("Next: Item: " + data[i] + "\n");
}

return sb.toString();
}
}

# Main.java

public class Main {

public static void main(String[] args) {

BestDataContainer<Animal> bdc = new BestDataContainer<>(10);

bdc.add(new Animal("Bear"));
bdc.add(new Animal("Dog"));
bdc.add(new Animal("Eagle"));
bdc.add(new Animal("Frog"));
bdc.add(new Animal("Jaguar"));

System.out.println(bdc);

bdc.remove(2);

System.out.println(bdc);

bdc.remove(new Animal("Frog"));

System.out.println(bdc);

System.out.println(bdc.get(2));
}
}

# 결과

Next: Item: Animal, Bear

Next: Item: Animal, Dog

Next: Item: Animal, Eagle

Next: Item: Animal, Frog

Next: Item: Animal, Jaguar

Next: Item: Animal, Bear

Next: Item: Animal, Dog

Next: Item: Animal, Frog

Next: Item: Animal, Jaguar

Next: Item: Animal, Bear

Next: Item: Animal, Dog

Next: Item: Animal, Jaguar

class Animal, Jaguar