1.迭代器接口实现
package com.zhaochao; public interface Iterator<E> { boolean hasNext(); E next(); boolean delete(); boolean modify(E e); int index(); }
2.List接口实现
package com.zhaochao; public interface List<E> { //链表大小 int size(); //链表是否为空 boolean isEmpty(); boolean contains(Object o); Iterator<E> iterator(); Object[] toArray(); <T> T[] toArray(T[] a); boolean add(E e); boolean remove(Object o); boolean containsAll(List<?> c); boolean addAll(List<? extends E> c); boolean addAll(int index, List<? extends E> c); boolean removeAll(List<?> c); boolean retainAll(List<?> c); void clear(); boolean equals(Object o); int hashCode(); E get(int index); E set(int index, E element); void add(int index, E element) ; E remove(int index); int indexOf(E o); int lastIndexOf(E o); List<E> subList(int fromIndex, int toIndex); }3.异常类实现
package com.zhaochao; public class IndexOutOfBoundsException extends RuntimeException { private static final long serialVersionUID = 234122996006267687L; /** * Constructs an <code>IndexOutOfBoundsException</code> with no * detail message. */ public IndexOutOfBoundsException() { super(); } /** * Constructs an <code>IndexOutOfBoundsException</code> with the * specified detail message. * * @param s the detail message. */ public IndexOutOfBoundsException(String s) { super(s); } }4.顺序结构单链表实现
package com.zhaochao; import java.util.Arrays; public class LinearList<E> implements List<E> { final static int INITIAL_CAPACITY=100; final static int INCREMENT_SIZE=10; transient Object [] item; transient int capacity=0; transient int length=0; LinearList(){ this.item=new Object[INITIAL_CAPACITY]; this.capacity=INITIAL_CAPACITY; } LinearList(List<E>list){ this.length=list.size(); this.capacity=this.length; this.item=list.toArray(); } @Override public int size() { // TODO Auto-generated method stub return this.length; } @Override public boolean isEmpty() { // TODO Auto-generated method stub return this.length==0; } @Override public boolean contains(Object o) { // TODO Auto-generated method stub return indexOf(o)!=-1; } @Override public Iterator<E> iterator() { // TODO Auto-generated method stub return new LinearIterator(); } private class LinearIterator implements Iterator<E>{ private int nowIndex; public LinearIterator() { // TODO Auto-generated constructor stub this.nowIndex=0; } @Override public boolean hasNext() { // TODO Auto-generated method stub return this.nowIndex<length; } @Override public E next() { // TODO Auto-generated method stub E e=(E) item[nowIndex]; nowIndex++; return e; } @Override public boolean delete() { // TODO Auto-generated method stub remove(nowIndex); return true; } @Override public boolean modify(E e) { // TODO Auto-generated method stub item[nowIndex]=e; return true; } @Override public int index() { // TODO Auto-generated method stub return nowIndex; } } @Override public Object[] toArray() { // TODO Auto-generated method stub Object []obj=new Object[length]; for(int i=0;i<length;i++) obj[i]=item[i]; return obj; } @Override public <T> T[] toArray(T[] a) { // TODO Auto-generated method stub if (a.length < length) // Make a new array of a's runtime type, but my contents: return (T[]) Arrays.copyOf(item, length, a.getClass()); System.arraycopy(item, 0, a, 0, length); if (a.length > length) a[length] = null; return a; } @Override public boolean add(E e) { // TODO Auto-generated method stub addLast(e); return true; } @Override public boolean remove(Object o) { // TODO Auto-generated method stub while(contains(o)){ remove(contains(o)); } return true; } @Override public boolean containsAll(List<?> c) { // TODO Auto-generated method stub boolean flag=true; Iterator it=c.iterator(); while(it.hasNext()){ flag=flag&&contains(it.next()); } return flag; } @Override public boolean addAll(List<? extends E> c) { // TODO Auto-generated method stub Iterator it=c.iterator(); while(it.hasNext()){ add((E)it.next()); } return true; } @Override public boolean addAll(int index, List<? extends E> c) { // TODO Auto-generated method stub Iterator it=c.iterator(); while(it.hasNext()){ add(index++,(E)it.next()); } return true; } @Override public boolean removeAll(List<?> c) { // TODO Auto-generated method stub Iterator it=c.iterator(); while(it.hasNext()){ if(contains(it.next())) remove(it.next()); } return true; } @Override public boolean retainAll(List<?> c) { // TODO Auto-generated method stub Iterator it=this.iterator(); while(it.hasNext()){ E e=(E) it.next(); if(!c.contains(e)) remove(e); } return true; } @Override public void clear() { // TODO Auto-generated method stub this.item=new Object[INITIAL_CAPACITY]; this.capacity=INITIAL_CAPACITY; } @Override public E get(int index) { // TODO Auto-generated method stub checkIndex(index); return (E) item[index]; } @Override public E set(int index, E element) { // TODO Auto-generated method stub checkIndex(index); item[index]=element; return element; } @Override public void add(int index, E element) { // TODO Auto-generated method stub checkIndex(index); checkCapacity(); System.arraycopy(item, index, item, index+1,length-index); item[index]=element; length++; } @Override public E remove(int index) { // TODO Auto-generated method stub checkRomoveIndex(index); E e=(E) item[index]; System.arraycopy(item, index+1, item, index,length-index-1); length--; return e; } @Override public int indexOf(Object o) { // TODO Auto-generated method stub E e=(E)o; int index=-1; if(o!=null){ for(int i=0;i<length;i++){ if(item[i].equals(e)) index=i; } }else{ for(int i=0;i<length;i++){ if(item[i]==null) index=i; } } return index; } @Override public int lastIndexOf(Object o) { // TODO Auto-generated method stub E e=(E)o; int index=-1; if(o!=null){ for(int i=length-1;i>0;--i){ if(item[i].equals(e)) index=i; } }else{ for(int i=length-1;i>0;--i){ if(item[i]==null) index=i; } } return index; } @Override public List<E> subList(int fromIndex, int toIndex) { // TODO Auto-generated method stub checkRomoveIndex(fromIndex); checkRomoveIndex(toIndex); List<E> ll=new LinearList<E>(); for(int i=fromIndex;i<=toIndex;i++) ll.add(get(i)); return ll; } private void addLast(E e){ checkCapacity(); item[length]=e; length++; } private void checkCapacity(){ if(length>=capacity){ Object []obj=new Object[capacity+INCREMENT_SIZE]; obj=Arrays.copyOfRange(item,0, length-1); item=obj; capacity+=INCREMENT_SIZE; } } private void checkRomoveIndex(int index){ if(index<0||index>=length){ throw new IndexOutOfBoundsException(outOfBoundsMsg(index)); } } private void checkIndex(int index) { if(index<0||index>length){ throw new IndexOutOfBoundsException(outOfBoundsMsg(index)); } } private String outOfBoundsMsg(int index){ return "index:"+index+" length:"+length; } }
5.测试
package com.zhaochao; public class main { public static void main(String[] args) throws Exception { // TODO Auto-generated method stub List<Test> ls=new LinearList<Test>(); Test t=new Test(); for(int i=0;i<10;i++) ls.add(t); Iterator it=ls.iterator(); while(it.hasNext()){ System.out.println(it.next()); } } } class Test{ public static int a=0; public String toString(){ return String.valueOf(a++); } }
6.测试结果
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