java - 如何在 vector 中输入千人数据？

Question

嗨，我是java新手，我正在 vector 中添加对象，现在我正在添加两个对象，但是如果我想通过文件或数据库输入千人的数据，我现在该怎么做，我有三个类。代码如下:-

public class Customer {

    private int custid;
    private String custname;
    private float custsalary;

    public String toString() {
        StringBuffer buffer = new StringBuffer();
        buffer.append("Customer Id     :=" + custid+"\n");
        buffer.append("Customer Name   :=" + custname+"\n");
        buffer.append("Customer Salary :=" + custsalary+"\n");
        return buffer.toString();
    }

    public int getCustid() {
        return custid;
    }

    public void setCustid(int custid) {
        this.custid = custid;
    }

    public String getCustname() {
        return custname;
    }

    public void setCustname(String custname) {
        this.custname = custname;
    }

    public float getCustsalary() {
        return custsalary;
    }

    public void setCustsalary(float custsalary) {
        this.custsalary = custsalary;
    }

}

第二类是

package com.test.collection.list.vector.custom;

import java.util.Enumeration;
import java.util.Vector;

public class CustomerVector {

    public void custDetails(){

        Customer c1Obj = new Customer();
        c1Obj.setCustid(123);
        c1Obj.setCustname("Kb");
        c1Obj.setCustsalary(1000.34f);

        Customer c2Obj = new Customer();
        c2Obj.setCustid(456);
        c2Obj.setCustname("nv");
        c2Obj.setCustsalary(2000.34f);

        Vector<Customer> v = new Vector<Customer>();
        v.addElement(c1Obj);
        v.addElement(c2Obj);

        Enumeration<Customer> custEnum = v.elements();
        while (custEnum.hasMoreElements()) {
            Customer customer = custEnum.nextElement();
            System.out.println(customer);
        }

    }

}

这是我的客户端代码

package com.test.collection.list.vector.custom;

public class ClientCode {

    public static void main(String[] args) {
        CustomerVector custVectObj = new CustomerVector();
        custVectObj.custDetails();
    }
}

我的问题是，如果我想添加千人的数据，最简单有效的方法是什么

Answer 1

使用以下内容更改您的 CustomVector:

public class CustomerVector {

    Vector<Customer> v = null;

    public CustomVector(){
        v = new Vector<Customer>();
    }

    public void createCustomer(int id, String name, float salary){
        Customer c1Obj = new Customer();
        c1Obj.setCustid(id);
        c1Obj.setCustname(name);
        c1Obj.setCustsalary(salary);

        v.addElement(c1Obj);
    }
    public void custDetails(){

        Enumeration<Customer> custEnum = v.elements();
        while (custEnum.hasMoreElements()) {
            Customer customer = custEnum.nextElement();
            System.out.println(customer);
        }

    }

}

并在主程序中添加 vector

package com.test.collection.list.vector.custom;

public class ClientCode {

    public static void main(String[] args) {
        CustomerVector custVectObj = new CustomerVector();
        // Add Customers
        custVectObj.createCustomer(1,"joan",10.03f);
        custVectObj.custDetails();
    }
}

自动生成 1000 个不同元素的 main 方法:

package com.test.collection.list.vector.custom;

public class ClientCode {

    public static void main(String[] args) {
        CustomerVector custVectObj = new CustomerVector();
        // Add Customers
        for(int i = 0; i < 1000; i++){
            custVectObj.createCustomer(i,"name"+i,i);
        }
        custVectObj.custDetails();
    }
}

您可以使用Random class 来使测试套件更加不同。