No effective change - ArrayStack cleanup

This commit is contained in:
Robin Bygrave
2015-08-01 22:00:00 +12:00
parent 0d2615522f
commit da65256208
2 changed files with 170 additions and 67 deletions
@@ -10,80 +10,80 @@ import java.util.EmptyStackException;
*/
public class ArrayStack<E> {
private final ArrayList<E> list;
private final ArrayList<E> list;
/**
* Creates an empty Stack with an initial size.
*/
public ArrayStack(int size) {
this.list = new ArrayList<E>(size);
}
/**
* Creates an empty Stack with an initial size.
*/
public ArrayStack(int size) {
this.list = new ArrayList<E>(size);
}
/**
* Creates an empty Stack.
*/
public ArrayStack() {
this.list = new ArrayList<E>();
}
/**
* Creates an empty Stack.
*/
public ArrayStack() {
this.list = new ArrayList<E>();
}
/**
* Pushes an item onto the top of this stack.
*/
public E push(E item) {
list.add(item);
return item;
}
/**
* Pushes an item onto the top of this stack.
*/
public void push(E item) {
list.add(item);
}
/**
* Removes the object at the top of this stack and returns that object as
* the value of this function.
*/
public E pop() {
int len = list.size();
E obj = peek();
list.remove(len - 1);
return obj;
/**
* Removes the object at the top of this stack and returns that object as
* the value of this function.
*/
public E pop() {
int len = list.size();
if (len == 0) {
throw new EmptyStackException();
}
return list.remove(len - 1);
}
protected E peekZero(boolean retNull) {
int len = list.size();
if (len == 0) {
if (retNull) {
return null;
}
throw new EmptyStackException();
}
return list.get(len - 1);
protected E peekZero(boolean retNull) {
int len = list.size();
if (len == 0) {
if (retNull) {
return null;
}
throw new EmptyStackException();
}
return list.get(len - 1);
}
/**
* Returns the object at the top of this stack without removing it.
*/
public E peek() {
return peekZero(false);
}
/**
* Returns the object at the top of this stack without removing it.
* If the stack is empty this returns null.
*/
public E peekWithNull() {
return peekZero(true);
}
/**
* Tests if this stack is empty.
*/
public boolean isEmpty() {
return list.isEmpty();
}
/**
* Returns the object at the top of this stack without removing it.
*/
public E peek() {
return peekZero(false);
}
public int size(){
return list.size();
}
public boolean contains(Object o){
//noinspection SuspiciousMethodCalls
return list.contains(o);
}
/**
* Returns the object at the top of this stack without removing it.
* If the stack is empty this returns null.
*/
public E peekWithNull() {
return peekZero(true);
}
/**
* Tests if this stack is empty.
*/
public boolean isEmpty() {
return list.isEmpty();
}
public int size() {
return list.size();
}
public boolean contains(Object o) {
//noinspection SuspiciousMethodCalls
return list.contains(o);
}
}
@@ -0,0 +1,103 @@
package com.avaje.ebeaninternal.server.util;
import org.junit.Test;
import java.util.EmptyStackException;
import static org.assertj.core.api.Assertions.assertThat;
public class ArrayStackTest {
@Test
public void testPushPop() throws Exception {
ArrayStack<String> stack = new ArrayStack<String>();
stack.push("1");
stack.push("2");
stack.push("3");
assertThat(stack.pop()).isEqualTo("3");
assertThat(stack.pop()).isEqualTo("2");
assertThat(stack.pop()).isEqualTo("1");
}
@Test
public void testPushPop_given_stackInitialSizeExceeded() throws Exception {
ArrayStack<String> stack = new ArrayStack<String>(2);
stack.push("1");
stack.push("2");
stack.push("3");
assertThat(stack.pop()).isEqualTo("3");
assertThat(stack.pop()).isEqualTo("2");
assertThat(stack.pop()).isEqualTo("1");
}
@Test(expected = EmptyStackException.class)
public void testPop_given_emptyStack_throws() throws Exception {
ArrayStack<String> stack = new ArrayStack<String>();
stack.pop();
}
@Test(expected = EmptyStackException.class)
public void testPeek_given_empty_throws() throws Exception {
ArrayStack<String> stack = new ArrayStack<String>();
assertThat(stack.peek());
}
@Test
public void testPeek_given_notEmpty() throws Exception {
ArrayStack<String> stack = new ArrayStack<String>();
stack.push("1");
assertThat(stack.peek()).isEqualTo("1");
}
@Test
public void testPeekWithNull() throws Exception {
ArrayStack<String> stack = new ArrayStack<String>();
assertThat(stack.peekWithNull()).isNull();
stack.push("1");
assertThat(stack.peekWithNull()).isEqualTo("1");
}
@Test
public void testIsEmpty() throws Exception {
ArrayStack<String> stack = new ArrayStack<String>();
assertThat(stack.isEmpty()).isTrue();
stack.push("1");
assertThat(stack.isEmpty()).isFalse();
}
@Test
public void testSize() throws Exception {
ArrayStack<String> stack = new ArrayStack<String>();
assertThat(stack.size()).isEqualTo(0);
stack.push("1");
assertThat(stack.size()).isEqualTo(1);
stack.push("w");
assertThat(stack.size()).isEqualTo(2);
}
@Test
public void testContains() throws Exception {
ArrayStack<String> stack = new ArrayStack<String>();
stack.push("1");
assertThat(stack.contains("1")).isTrue();
assertThat(stack.contains("2")).isFalse();
}
}