Question

我正在开发一个使用外部文件的程序。该计划必须：编写程序将调查结果读入三个数组，回显打印数据并执行并输出以下分析：

统计调查中包含的住户数量并打印显示所读数据的三栏表（假设不超过25户）
计算家庭平均收入，并列出每个家庭的识别号码和收入超过平均值。
确定收入低于贫困水平的家庭百分比。贫困水平收入可使用以下公式计算：p = $ 3750.00 + $ 750.00 *（m-2）其中m是每个家庭的成员数。

这是我到目前为止所做的，但它似乎不起作用（我必须要上课）：

import java.io.*;
import java.util.Scanner;
public class main
{
    public static void main(String[] args) throws Exception
    {
        Scanner sf = new Scanner(new FileInputStream("survey2.dat"));

        String[] filePaths = { "D:/survey2.dat" };
        SurveyCollection surveys = new SurveyCollection();
        Runner runner = new Runner();
        runner.load(filePaths, surveys);
        runner.printHouseholdIncomeExceedingAverage(surveys);
        runner.printouseholdBelowPoverty(surveys);
        //print(surveys);

        System.exit(0);
    }
}

import java.io.*;
import java.util.Scanner;
public class Runner
{
   public static void load(String[] filePaths, SurveyCollection surveys)throws Exception {
    for (int i = 0; i < filePaths.length; i++) {
      Scanner fileIn = null;
      try {
        fileIn = new Scanner(new FileReader(filePaths[i]));
        while (fileIn.hasNextLine()) {
          String line = fileIn.nextLine();
          surveys.setSurvey(line);
        }
      } catch (Exception ex) {
        ex.printStackTrace();
      } /*finally {
        fileIn.close();
      }*/
    }
  }

  public static void printHouseholdIncomeExceedingAverage(
      SurveyCollection surveys) {
    int size = surveys.getNumberOfHousehold();
    double average = surveys.getAverageIncome();
    String message = "Households with income exceeding an average income of %,.2f%n";
    System.out.printf(message, average);
    System.out.println("Id   Income Member");
    for (int i = 0; i < size; i++) {
      if (surveys.getIncomeByIdx(i) > average) {
        System.out.println(surveys.formattedString(i));
      }
    }
  }

  /**
   * design for debug
   * @param surveys
   */
  private static void print(SurveyCollection surveys) {
    int size = surveys.getNumberOfHousehold();
    System.out.println();
    for (int i = 0; i < size; i++) {
      System.out.println(surveys.formattedString(i));
    }
  }

  public static void printouseholdBelowPoverty(SurveyCollection surveys) {
    int size = surveys.getNumberOfHousehold();
    int count = 0;
    System.out.println();
    for (int i = 0; i < size; i++) {
      if (surveys.isInPoverty(i)) {
        System.out.println(surveys.formattedString(i));
        count++;
      }
    }
    String message = "Percent of households below poverty level = %f%n";
    System.out.printf(message, ((double) count / (double) size));
  }
}

class SurveyCollection {
  final int MAX = 30;
  private int idx = 0;
  private int sumOfIncome = 0;
  private String[] surveyIds = new String[MAX];
  private int[] incomes = new int[MAX];
  private int[] members = new int[MAX];

  public void setSurvey(String value) {
    if (idx < MAX) {
      String[] fields = value.split(" ");
      surveyIds[idx] = fields[0];
      incomes[idx] = Integer.parseInt(fields[1]);
      members[idx] = Integer.parseInt(fields[2]);
      sumOfIncome += incomes[idx];
      idx++;
    }
  }

  public int getNumberOfHousehold() {
    return this.idx;
  }

  public double getAverageIncome() {
    return (double) sumOfIncome / getNumberOfHousehold();
  }

  public int getIncomeByIdx(int idx) {
    return incomes[idx];
  }

  public String formattedString(int idx) {
    String style = "%s %d %d";
    return String.format(style, this.surveyIds[idx], this.incomes[idx], this.members[idx]);
  }

  public boolean isInPoverty(int idx) {
    boolean result = false;
    int threadhold = (3750 + 750 * members[idx]);
    result = incomes[idx] <= threadhold;
    return result;
  }

}

我做错了什么？

外部文件：

1041 12180 4
1062 13240 3
1327 19800 2
1483 22458 8
1900 17000 2
2112 18125 7
2345 15623 2
3210 3200 6
3600 6500 5
3601 11970 2
4725 8900 3
6217 10000 2
9280 6200 1

输出应与此类似：

id     income    members
1041     12180       4
1062     13240       3
1327     19800       2
1483     22458       8
1900     17000       2
2112     18125       7
2345     15623       2
3210       3200       6
3600       6500       5
3601     11970       2
4725       8900       3
6217     10000       2
9280       6200       1


Households with income exceeding an average income of 12707.4

 id     income    members
1062     13240       3
1327     19800       2
1483     22458       8
1900     17000       2
2112     18125       7
2345     15623       2

Percent of households below poverty level = 0.0769231

Answer 1

当我将整个文件路径传递给runner.load方法时，我得到一些输出。

    String fileName = "survey2.dat";
    String filePaths[] = {"C:\\Users\\Neal\\Desktop\\" + fileName};


        Households with income exceeding an average income of 12,707.38
Id   Income Member
1062 13240 3
1327 19800 2
1483 22458 8
1900 17000 2
2112 18125 7
2345 15623 2

3210 3200 6
3600 6500 5
Percent of households below poverty level = 0.153846

House Hold Income报告 - java

1 个答案: