我的项目有OOP程序,我无法理解为什么会出错。
这个程序就像一个投票系统,但只是简单地使用键盘输入。但在此之前,我想分别使用Voter vote = new Voter("String here");
和Candidates cand = new Candidates("String");
来展示以前的选民,然后是候选人及其排名。
无论我如何再次查看我的代码,我仍然会遇到同样的错误。我是Java的新手,如果有人可以同时解释和回答我会有所帮助。如果有人看到我说的错误,它会很棒。谢谢!
我的代码,
候选班级:
public class Candidates
{
public String candName;
private int position;
private int totalVotes;
public void Candidate (String candName, int position, int totalVotes)
{
this.candName = candName;
this.position = position;
this.totalVotes = totalVotes;
}
public void setDetails (String candName, int position, int totalVotes)
{
this.candName = candName;
this.position = position;
this.totalVotes = totalVotes;
}
public String getCandName()
{
return candName;
}
public int getPosition()
{
return position;
}
public int getTotalVotes()
{
return totalVotes;
}
}
选民班:
public class Voter
{
private String name;
private int votNum;
private int precint;
public Voter(String name, int votNum, int precint, double bDay)
{
this.name = name;
this.votNum = votNum;
this.precint = precint;
}
public void setDetails(String name, int votNum, int precint)
{
this.name = name;
this.votNum = votNum;
this.precint = precint;
}
public String getName()
{
return name;
}
public int getVotNum()
{
return votNum;
}
public int getPrecint()
{
return precint;
}
public Voter toString()
{
StringBuilder sb = new StringBuilder();
sb.append(name).append(" ");
sb.append(votNum).append(" ");
sb.append(precint).append(" ");
sb.append("Voter's Name: ").append(" ");
sb.append("Voter's ID number: ").append(" ");
sb.append("Precint: ").append(" ");
return sb.toString();
}
}
主要班级:
import java.util.Scanner;
public class voteDemo
{
public static void main(String[] args)
{
System.out.println("Previous voter's info: ");
Voter vot1 = new Voter("Name1", 131, 01);
Voter vot2= new Voter("Name2", 265, 02);
Voter vot3= new Voter("Name3", 343, 01);
System.out.println(vot1);
System.out.println(vot2);
System.out.println(vot3);
System.out.println("The Candidates: ");
Candidates cand1 = new Candidates("Candidate1", 1, 19000);
Candidates cand2 = new Candidates("Candidate2" , 2, 17000);
Candidates cand3 = new Candidates("Candidate3", 3, 12000);
System.out.println(cand1);
System.out.println(cand2);
System.out.println(cand3);
Scanner kb = new Scanner(System.in);
System.out.println("Enter Voter's Name: ");
String name = kb.nextLine();
System.out.println("Enter Voter's ID: ");
int votNum = kb.nextInt();
System.out.println("Enter Precint: ");
int precint = kb.nextInt();
do
{
System.out.println("\n\nSelect Candidate for Senator:");
System.out.println("1 - Choice1");
System.out.println("2 - Choice2");
System.out.println("3 - Choice3");
System.out.println("4 - Choice4");
System.out.println("5 - Choice5");
System.out.print("\nEnter choice: ");
choice = kb.nextInt();
switch(choice)
{
case 1:
System.out.println("Name: " + name);
System.out.println("Voter ID: " + votNum);
System.out.println("Precint No.: " + precint);
System.out.println("Senator of choice: Choice1");
break;
case 2:
System.out.println("Name: " + name);
System.out.println("Voter ID: " + votNum);
System.out.println("Precint No.: " + precint);
System.out.println("Senator of choice: Choice2");
break;
case 3:
System.out.println("Name: " + name);
System.out.println("Voter ID: " + votNum);
System.out.println("Precint No.: " + precint);
System.out.println("Senator of choice: Choice3");
break;
case 4:
System.out.println("Name: " + name);
System.out.println("Voter ID: " + votNum);
System.out.println("Precint No.: " + precint);
System.out.println("Senator of choice: Choice4");
break;
case 5:
System.out.println("Name: " + name);
System.out.println("Voter ID: " + votNum);
System.out.println("Precint No.: " + precint);
System.out.println("Senator of choice: Choice5");
break;
default:
System.out.println("Error. Review your entries.");
break;
}
} while (choice != 5 );
System.out.println("Press Enter to confirm.");
}
}
我得到的错误:
必需:String,int,int,double found:String,int,int
原因:实际和正式的参数列表长度不同
在我的主要班级的第7,8,9和15,16,17行。voteDemo.java:47:错误:找不到符号 choice = kb.nextInt(); 在我的主要班级
答案 0 :(得分:2)
简单来说,这意味着你有一个需要N个参数的方法调用,但你给它的参数数量是错误的; e.g。
public void setFoo(int arg) { ... }
// using it correctly
setFoo(24);
// using it incorrectly
setFoo(); // compilation error - wrong number of args
setFoo(42, 43); // compilation error - wrong number of args
您可以使用构造函数和new
获得相同的功能......正如您所做的那样。
public Voter(String name, int votNum, int precint, double bDay)
Voter vot1 = new Voter("Name1", 131, 01);
请参阅?
您使用4个参数声明它,并尝试将其与3一起使用。
这一个......
voteDemo.java:47:错误:找不到符号选择= kb.nextInt();在我的主要班级
您尚未声明choice
。您刚刚分配了一个尚未声明的变量。不能用Java做到这一点。必须显式声明每个变量。
虽然我引起了你的注意,但在Java数字文字中加上前导零通常一个坏主意。为什么?因为前导零告诉Java编译器您使用的是八进制而不是十进制。所以011
实际上意味着九个,而不是十一个!除非表示以八进制编写数字,否则不要使用前导零。