Tutoriais - Programação Orientada a ObjetosDesenvolva um programa que realize a iteração sobre os elementos de uma matriz, utilizando o padrão de projeto Iterator.
/*************************************************************************
* Copyright (C) 2009/2025 - Cristiano Lehrer (cristiano@ybadoo.com.br) *
* Ybadoo - Solucoes em Software Livre (ybadoo.com.br) *
* *
* Permission is granted to copy, distribute and/or modify this document *
* under the terms of the GNU Free Documentation License, Version 1.3 or *
* any later version published by the Free Software Foundation; with no *
* Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A *
* A copy of the license is included in the section entitled "GNU Free *
* Documentation License". *
* *
* Ubuntu 16.10 (GNU/Linux 4.8.0-39-generic) *
* OpenJDK Version "1.8.0_121" *
* OpenJDK 64-Bit Server VM (build 25.121-b13, mixed mode) *
*************************************************************************/
package com.ybadoo.tutoriais.poo.tutorial10.exercicio32;
import java.util.NoSuchElementException;
/**
* Interface com os metodos de navegacao pela iteracao
*
* Iterator define uma interface para acessar e percorrer elementos
* (Gamma, 2000)
*
* @param <T> tipo de elemento retornado por esse iterador
*/
public interface Iterator<T>
{
/**
* Retornar true se a iteracao tem mais elementos
*
* @return true se a iteracao tem mais elementos
*/
public boolean hasNext();
/**
* Retornar o proximo elemento na iteracao
*
* @return proximo elemento na iteracao
* @throws NoSuchElementException se a iteracao nao tem mais elementos
*/
public T next();
}/*************************************************************************
* Copyright (C) 2009/2025 - Cristiano Lehrer (cristiano@ybadoo.com.br) *
* Ybadoo - Solucoes em Software Livre (ybadoo.com.br) *
* *
* Permission is granted to copy, distribute and/or modify this document *
* under the terms of the GNU Free Documentation License, Version 1.3 or *
* any later version published by the Free Software Foundation; with no *
* Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A *
* A copy of the license is included in the section entitled "GNU Free *
* Documentation License". *
* *
* Ubuntu 16.10 (GNU/Linux 4.8.0-39-generic) *
* OpenJDK Version "1.8.0_121" *
* OpenJDK 64-Bit Server VM (build 25.121-b13, mixed mode) *
*************************************************************************/
package com.ybadoo.tutoriais.poo.tutorial10.exercicio32;
/**
* Interface para retornar um iterador
*
* Aggregate define uma interface para a criacao de um objeto
* Iterator (Gamma, 2000)
*
* @param <T> tipo de elemento manuseado pelo iterador
*/
public interface Container<T>
{
/**
* Retornar o iterador do conjunto de elementos
*
* @return iterador do conjunto de elementos
*/
public Iterator<T> getIterator();
}/*************************************************************************
* Copyright (C) 2009/2025 - Cristiano Lehrer (cristiano@ybadoo.com.br) *
* Ybadoo - Solucoes em Software Livre (ybadoo.com.br) *
* *
* Permission is granted to copy, distribute and/or modify this document *
* under the terms of the GNU Free Documentation License, Version 1.3 or *
* any later version published by the Free Software Foundation; with no *
* Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A *
* A copy of the license is included in the section entitled "GNU Free *
* Documentation License". *
* *
* Ubuntu 16.10 (GNU/Linux 4.8.0-39-generic) *
* OpenJDK Version "1.8.0_121" *
* OpenJDK 64-Bit Server VM (build 25.121-b13, mixed mode) *
*************************************************************************/
package com.ybadoo.tutoriais.poo.tutorial10.exercicio32;
import java.util.NoSuchElementException;
/**
* Representacao de uma matriz de elementos
*
* ConcreteAggregate implementa a interface de criacao do
* Iterator para retornar uma instancia do ConcreteIterator
* apropriado (Gamma, 2000)
*
* @param <T> tipo de elemento armazenado na matriz
*/
public class Matrix<T> implements Container<T>
{
/**
* Iterador para uma matriz de elementos
*
* ConcreteIterator implementa a interface de Iterator e mantem
* o controle da posicao corrente no percurso do agregado
* (Gamma, 2000)
*
* @param <T> tipo de elemento retornado por esse iterador
*/
private class MatrixIterator implements Iterator<T>
{
/**
* Linha atual da matriz
*/
private int line;
/**
* Coluna atual da matriz
*/
private int column;
/**
* Inicializar o iterador
*/
public MatrixIterator()
{
line = 0;
column = 0;
}
/* (non-Javadoc)
* @see com.ybadoo.tutoriais.poo.tutorial10.exercicio32.
* Iterator#hasNext()
*/
@Override
public boolean hasNext()
{
return line < values.length;
}
/* (non-Javadoc)
* @see com.ybadoo.tutoriais.poo.tutorial10.exercicio32.
* Iterator#next()
*/
@Override
public T next()
{
T temp;
try
{
temp = values[line][column];
}
catch(IndexOutOfBoundsException exception)
{
throw new NoSuchElementException(exception.getMessage());
}
column = column + 1;
if(column >= values[line].length)
{
column = 0;
line = line + 1;
}
return temp;
}
}
/**
* Valores armazenados na matriz
*/
private T[][] values;
/**
* Construtor para inicializar a matriz
*
* @param values valores armazenados na matriz
*/
public Matrix(T[][] values)
{
this.values = values;
}
/* (non-Javadoc)
* @see com.ybadoo.tutoriais.poo.tutorial10.exercicio32.
* Container#getIterator()
*/
@Override
public Iterator<T> getIterator()
{
return new MatrixIterator();
}
}/*************************************************************************
* Copyright (C) 2009/2025 - Cristiano Lehrer (cristiano@ybadoo.com.br) *
* Ybadoo - Solucoes em Software Livre (ybadoo.com.br) *
* *
* Permission is granted to copy, distribute and/or modify this document *
* under the terms of the GNU Free Documentation License, Version 1.3 or *
* any later version published by the Free Software Foundation; with no *
* Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A *
* A copy of the license is included in the section entitled "GNU Free *
* Documentation License". *
* *
* Ubuntu 16.10 (GNU/Linux 4.8.0-39-generic) *
* OpenJDK Version "1.8.0_121" *
* OpenJDK 64-Bit Server VM (build 25.121-b13, mixed mode) *
*************************************************************************/
package com.ybadoo.tutoriais.poo.tutorial10.exercicio32;
/**
* Classe responsavel pela execucao do padrao Iterator
*/
public class Application
{
/**
* Construtor para inicializar a execucao do padrao Iterator
*/
private Application()
{
}
/**
* Metodo principal da linguagem de programacao Java
*
* @param args argumentos da linha de comando (nao utilizado)
*/
public static void main(String[] args)
{
Integer[][] values = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}};
Matrix<Integer> matrix = new Matrix<Integer>(values);
Iterator<Integer> iterator = matrix.getIterator();
while(iterator.hasNext())
{
System.out.println(iterator.next());
}
}
}Gamma, Erich. (2000). Padrões de Projeto: soluções reutilizáveis de software orientado a objetos. Porto Alegre: Bookman. 364 páginas.
Ybadoo - Soluções em Software Livre • Copyright 2009/2025 • 