Java implements sequential storage operations for linear tables

Create a new interface: IList, define the operation:

package com.list;

public interface IList {

	public void clear();	//清空线性表
	
	public boolean isEmpty();
	
	public int length();	//获取元素个数
	
	public Object get(int i) throws Exception;	//获取第 i+1 个元素，i从0开始
	
	public void insert(int i, Object x) throws Exception;
	
	public void remove(int i) throws Exception;
	
	public int indexOf(Object x);
	
	public void display();
}

Create a new SqList class to implement the method of the IList interface:

package com.list;

public class SqList implements IList {

	public Object[] listElem;	//线性表存储空间
	public int curLength;		//线性表当前长度
	
	public SqList(int maxSize) {
		curLength = 0;
		listElem = new Object[maxSize];
	}
	
	@Override
	public void clear() {
		curLength = 0;
	}

	@Override
	public boolean isEmpty() {
		return curLength == 0;
	}

	@Override
	public int length() {
		return curLength;
	}

	@Override
	public Object get(int i) throws Exception {
		if (curLength == 0) {
			throw new Exception("当前线性表为空 --> " + curLength);
		}
		if (i < 0 || i >= curLength) {
			throw new Exception("第" + i + "个元素不存在");
		}
		return listElem[i];
	}

	@Override
	public void insert(int i, Object x) throws Exception {
		if (curLength == listElem.length) {
			throw new Exception("顺序表已满");
		}
		if (i < 0 || i >= listElem.length) {
			throw new Exception("插入位置不合法");
		}
		for (int j = curLength; j > i; j--) {
			listElem[j] = listElem[j - 1];
		}
		listElem[i] = x;
		curLength++;
	}

	@Override
	public void remove(int i) throws Exception {
		if (i < 0 || i >= curLength) {
			throw new Exception("删除位置不合法");
		}
		for (int j = i; j < curLength - 1; j++) {
			listElem[j] = listElem[j + 1];
		}
		curLength--;
	}

	@Override
	public int indexOf(Object x) {
		int j = 0;
		
		while (j < curLength && !listElem[j].equals(x)) {
			j++;
		}
		if (j < curLength) {
			return j;
		}else {
			return -1;
		}
	}

	@Override
	public void display() {
		for (int j = 0; j < curLength; j++) {
			System.err.println(listElem[j]);
		}
	}
	
	public static void main(String[] args) {
		SqList list = new SqList(10);
		
		try {
			list.insert(0, 1);
			list.insert(0, 2);
		} catch (Exception e) {
			e.printStackTrace();
		}
		
		list.display();
	}

}

Summary of linear table sequential storage:

    advantage:

    1. There is no need to add additional storage space for representing the relationship between elements;

    2. You can quickly access elements at any position in the table. (time complexity is O(1))

    shortcoming:

    1. Insertion and deletion operations require moving a large number of elements; (time complexity is O(N))

    2. When the length of the linear table changes greatly, the storage space capacity cannot be determined;

    3. It is easy to cause "fragmentation" of storage space.