这是我第一次在这里发帖，而且我还是很擅长编程（不久前刚刚开始使用Java），所以你们可以给我一些关于如何解决我的问题的建议将不胜感激！我希望我在第一篇文章中遵循这些指导原则！
在这个项目的宏伟计划中，我试图对我的“团队”进行排序，以确定谁拥有与马拉松相关的最多“圈数，骑手和捐赠”。 Team类由Rider对象组成。
这是我使用Team类中存在的方法迭代我的Team数组的循环。
ArrayList<Team> team = new ArrayList<Team>();
for(int i=0; i<team.size(); i++){
team.get(i).mostDonations(team);
team.get(i).mostLaps(team);
team.get(i).mostRiders(team);
}
这是我的团队课程。它充满了所需的构造函数，设置器和getter，以及计算总数的方法。但我认为下面应该是相关的代码行。 （如果我要留下任何东西，请告诉我！）
public class Team {
private String teamName;
private String teamAbbreviation;
private ArrayList<Riders> riders = new ArrayList<Riders>();
DecimalFormat decimal = new DecimalFormat("#0.00");
public double totalDonations(){
double totalDonations = 0;
for(int i=0; i < riders.size(); i++){
totalDonations += riders.get(i).getAmount();
}
return totalDonations;
}
public int totalLaps(){
int totalLaps = 0;
for (int i = 0; i < riders.size(); i++){
totalLaps += riders.get(i).getLaps();
}
return totalLaps;
}
public int totalRiders(){
int totalRiders = 0;
for (int i =0; i < riders.size(); i++){
totalRiders += riders.size();
}
return totalRiders;
}
public void mostLaps(ArrayList<Team> Teams){
int max = 0;
int indexOfMax = 0;
for(int i=0; i < Teams.size(); i++){
if(Teams.get(i).totalDonations() > max){
max = Teams.get(i).totalLaps();
indexOfMax = i;
}
}
System.out.println("The team with the most laps is: " + Teams.get(indexOfMax).getName() + "!");
}
public void mostRiders(ArrayList<Team> Teams){
int max = 0;
int indexOfMax = 0;
for(int i=0; i < Teams.size(); i++){
if(Teams.get(i).totalRiders() > max){
max = Teams.get(i).totalRiders();
indexOfMax = i;
}
}
System.out.println("The team with the most riders is: " + Teams.get(indexOfMax).getName() + "!");
}
public void mostDonations(ArrayList<Team> Teams){
double max = 0.0;
int indexOfMax = 0;
for(int i=0; i < Teams.size(); i++){
if(Teams.get(i).totalDonations() > max){
max = Teams.get(i).totalDonations();
indexOfMax = i;
}
}
System.out.println("The team with the most donations is: " + Teams.get(indexOfMax).getName() + "!");
}
这是我的Rider课程。
public class Riders {
private String name;
private String hometown;
private String id;
private int laps;
private double amountRaised;
public Riders(){
name = "";
hometown = "";
id = "";
laps = 0;
amountRaised = 0.0;
}
public Riders(String Name, String Hometown, String ID, int Laps){
name = Name;
hometown = Hometown;
id = ID;
laps = Laps;
amountRaised = 0.0;
}
public void setName(String Name){
name = Name;
}
public void setHometown(String Hometown){
hometown = Hometown;
}
public void setAbbreviation(String ID){
id = ID;
}
public void setLaps(int Laps){
laps = Laps;
}
public void setAmount(double Amount){
amountRaised = Amount;
}
public String getName(){
return name;
}
public String getHometown(){
return hometown;
}
public String getID(){
return id;
}
public int getLaps(){
return laps;
}
public double getAmount(){
return amountRaised;
}
public String toString(){
String s = "Rider Name: " + name + "\nHometown: " + hometown + "\nID: " + id + "\nLaps: " + laps;
return s;
}
}
然而，输出如下所示：
捐赠最多的团队是：斑马军队成员！
圈数最多的球队是：Xtremely Together！
拥有最多车手的车队是：斑马军队成员！
捐赠最多的团队是：斑马军队成员！
圈数最多的球队是：Xtremely Together！
拥有最多车手的车队是：斑马军队成员！
捐赠最多的团队是：斑马军队成员！
圈数最多的球队是：Xtremely Together！
拥有最多车手的车队是：斑马军队成员！
捐赠最多的团队是：斑马军队成员！
圈数最多的球队是：Xtremely Together！
拥有最多车手的车队是：斑马军队成员！
捐赠最多的团队是：斑马军队成员！
圈数最多的球队是：Xtremely Together！
拥有最多车手的车队是：斑马军队成员！
捐赠最多的团队是：斑马军队成员！
圈数最多的球队是：Xtremely Together！
拥有最多车手的车队是：斑马军队成员！
捐赠最多的团队是：斑马军队成员！
圈数最多的球队是：Xtremely Together！
拥有最多车手的车队是：斑马军队成员！
捐赠最多的团队是：斑马军队成员！
圈数最多的球队是：Xtremely Together！
拥有最多车手的车队是：斑马军队成员！
捐赠最多的团队是：斑马军队成员！
圈数最多的球队是：Xtremely Together！
拥有最多车手的车队是：斑马军队成员！
捐赠最多的团队是：斑马军队成员！
圈数最多的球队是：Xtremely Together！
拥有最多车手的车队是：斑马军队成员！
我很困惑为什么它一遍又一遍地打印相同的三行。我希望有人能指出我正确的方向。
答案 0 :(得分：0)
以下循环遍历SELECT q2."DATE", NVL(q."TOTAL AMOUNT FUNDED PER DAY", 0) AS "TOTAL AMOUNT FUNDED PER DAY"
FROM (
SELECT TRUNC (funddate, 'DD') "DATE",
NVL(SUM (amount),0) "TOTAL AMOUNT FUNDED PER DAY"
FROM purchases
WHERE empid= 1234 AND amount < 0
GROUP BY TRUNC (funddate, 'DD')
) q
RIGHT JOIN (
SELECT TRUNC (SYSDATE - ROWNUM) "DATE"
FROM DUAL CONNECT BY ROWNUM < 100
) q2
on q2."DATE" = q."DATE"
，并为每个ArrayList<Team>项打印三行。
Team现在，您也通过上述循环传递for(int i=0; i<team.size(); i++){
team.get(i).mostDonations(team);
team.get(i).mostLaps(team);
team.get(i).mostRiders(team);
}
。
team更新：快速方法是删除调用这三种方法的for循环。
for(int i=0; i < Teams.size(); i++){
if(Teams.get(i).totalDonations() > max){
max = Teams.get(i).totalDonations(); // always goes for the max team object
indexOfMax = i;
}
}
我将验证这对您的代码有多高效。
答案 1 :(得分：0)
您对编程的了解越多，设计就越重要。我仍然认为你的课程设计糟糕。我已经创建了一个小应用来展示更好的设计。
团队课程：
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package javaapplication16;
import java.util.*;
/**
*
* @author Sedrick
*/
public class Team {
private String teamName;
private List<String> playerName;
private List<Integer> age;
private int numOfMembers;
private double membersAverageAge;
public Team(String teamName, List<String> playerName, List<Integer> age)
{
this.teamName = teamName;
this.playerName = playerName;
this.age = age;
this.numOfMembers = playerName.size();
this.membersAverageAge = caculateAvgAge(this.age);
}
private static double caculateAvgAge(List<Integer> age)
{
int sum = 0;
if (age.size() > 0) {
for (int i = 0; i < age.size(); i++) {
sum += age.get(i);
}
}
else {
return Double.NaN;
}
return (double) sum / (double) age.size();
}
/**
* @return the teamName
*/
public String getTeamName()
{
return teamName;
}
/**
* @param teamName the teamName to set
*/
public void setTeamName(String teamName)
{
this.teamName = teamName;
}
/**
* @return the playerName
*/
public List<String> getPlayerName()
{
return playerName;
}
/**
* @param playerName the playerName to set
*/
public void setPlayerName(List<String> playerName)
{
this.playerName = playerName;
}
/**
* @return the age
*/
public List<Integer> getAge()
{
return age;
}
/**
* @param age the age to set
*/
public void setAge(List<Integer> age)
{
this.age = age;
}
/**
* @return the numOfMembers
*/
public int getNumOfMembers()
{
return numOfMembers;
}
/**
* @param numOfMembers the numOfMembers to set
*/
public void setNumOfMembers(int numOfMembers)
{
this.numOfMembers = numOfMembers;
}
/**
* @return the membersAverageAge
*/
public double getMembersAverageAge()
{
return membersAverageAge;
}
/**
* @param membersAverageAge the membersAverageAge to set
*/
public void setMembersAverageAge(double membersAverageAge)
{
this.membersAverageAge = membersAverageAge;
}
}
主类：
import java.util.*;
/**
*
* @author Sedrick
*/
public class JavaApplication16 {
/**
* @param args the command line arguments
*/
public static void main(String[] args)
{
// TODO code application logic here
List<String> cowPlayer = new ArrayList();
List<Integer> cowPlayerAge = new ArrayList();
cowPlayer.add("Tim");
cowPlayerAge.add(20);
cowPlayer.add("Jane");
cowPlayerAge.add(23);
cowPlayer.add("Kim");
cowPlayerAge.add(25);
cowPlayer.add("Chris");
cowPlayerAge.add(10);
Team cow = new Team("Cows", cowPlayer, cowPlayerAge);
List<String> frogPlayer = new ArrayList();
List<Integer> frogPlayerAge = new ArrayList();
frogPlayer.add("Dana");
frogPlayerAge.add(21);
frogPlayer.add("Jack");
frogPlayerAge.add(19);
frogPlayer.add("Jill");
frogPlayerAge.add(30);
Team frog = new Team("Frogs", frogPlayer, frogPlayerAge);
System.out.println(cow.getTeamName() + " info");
System.out.println("\tNumber of members: " + cow.getNumOfMembers());
System.out.println("\tNumber of members: " + cow.getMembersAverageAge());
System.out.println("\tPlayers Name and Age");
for (int i = 0; i < cow.getPlayerName().size(); i++) {
System.out.println("\t\t" + cow.getPlayerName().get(i) + " - " + cow.getAge().get(i));
}
System.out.println(frog.getTeamName() + " info");
System.out.println("\tNumber of members: " + frog.getNumOfMembers());
System.out.println("\tNumber of members: " + frog.getMembersAverageAge());
System.out.println("\tPlayers Name and Age");
for (int i = 0; i < frog.getPlayerName().size(); i++) {
System.out.println("\t\t" + frog.getPlayerName().get(i) + " - " + frog.getAge().get(i));
}
List<Team> teams = new ArrayList();
teams.add(cow);
teams.add(frog);
System.out.println("Team with the most players: " + whichTeamHasTheMostPlayers(teams));
System.out.println("Team whose players average age is higher: " + whichTeamHasTheHighestAverageAge(teams));
}
//If there are more than one team with the same number of players this will not work correctly.
static private String whichTeamHasTheMostPlayers(List<Team> teams)
{
int mostPlayersIndex = 0;//assume the first team has the most players;
int amountOfPlayers = teams.get(0).getNumOfMembers();
for (int i = 1; i < teams.size(); i++) {
if (teams.get(i).getNumOfMembers() > amountOfPlayers) {
mostPlayersIndex = i;
amountOfPlayers = teams.get(i).getNumOfMembers();
}
}
return teams.get(mostPlayersIndex).getTeamName();
}
//If there are more than one team with the same average this will not work correctly.
static private String whichTeamHasTheHighestAverageAge(List<Team> teams)
{
int highestAvgIndex = 0;//assume the first team has the most players;
double teamAvg = teams.get(0).getMembersAverageAge();
for (int i = 1; i < teams.size(); i++) {
if (teams.get(i).getMembersAverageAge() > highestAvgIndex) {
highestAvgIndex = i;
teamAvg = teams.get(i).getMembersAverageAge();
}
}
return teams.get(highestAvgIndex).getTeamName();
}
}