我应该更改什么来使这个文件编译?
我在编程课程中,这个课程是我作业的一部分。 此文件分析名为“Names.txt”的文件中的数据,然后打印信息。 我收到编译错误,我想知道我需要更改或添加以使其成功编译。
这是我的代码:
import java.util.Scanner; import java.io.File; import java.io.FileNotFoundException; public class NameApp { public static void main(String[] args) { Scanner stdin = new Scanner(System.in); String selection, nameIn, nameIn2; Name name, name2; int decade; String first = "1", second = "2", third = "3", fourth = "4", fifth = "5", sixth = "6", seventh = "7", eighth = "8", ninth = "9", tenth = "10"; do { System.out.println("Enter the character corresponding to your selection:"); System.out.println("a - Print histogram for a name"); System.out.println("b - Compare two names in a decade"); System.out.println("c - Print top ten names for a decade"); System.out.println("d - Quit (display file anomalies)"); selection = stdin.next(); System.out.println("your selection: " + selection); if (selection.equalsIgnoreCase("a")) { System.out.println("Enter a name: "); nameIn = stdin.next(); name = nameIn.findName(); System.out.println("Histogram for name, " + name.getName()); } if (selection.equalsIgnoreCase("b")) { System.out.println("Enter a name: "); nameIn = stdin.next(); name = nameIn.findName(); System.out.println("Enter a name: "); nameIn2 = stdin.next(); name2 = nameIn.findName(); System.out.println("Enter number corresponding to your decade:"); System.out.println("1 - 1900-1909"); System.out.println("2 - 1910-1919"); System.out.println("1 - 1920-1929"); System.out.println("1 - 1930-1939"); System.out.println("1 - 1940-1949"); System.out.println("1 - 1950-1959"); System.out.println("1 - 1960-1969"); System.out.println("1 - 1970-1979"); System.out.println("1 - 1980-1989"); System.out.println("1 - 1990-1999"); System.out.println("1 - 2000-2005"); System.out.println("Enter a decade: "); decade = stdin.nextInt(); System.out.println("Data for " + name.getName()); System.out.println(name.getHistoLine(decade)); System.out.println("Date for " + name2.getName()); System.out.println(name2.getHistoLine(decade)); } if (selection.equalsIgnoreCase("C")) { System.out.println("Enter number corresponding to your decade:"); System.out.println("1 - 1900-1909"); System.out.println("2 - 1910-1919"); System.out.println("1 - 1920-1929"); System.out.println("1 - 1930-1939"); System.out.println("1 - 1940-1949"); System.out.println("1 - 1950-1959"); System.out.println("1 - 1960-1969"); System.out.println("1 - 1970-1979"); System.out.println("1 - 1980-1989"); System.out.println("1 - 1990-1999"); System.out.println("1 - 2000-2005"); System.out.println("Enter a decade: "); decade = stdin.nextInt(); System.out.println("Ten most popular names (male and female) during the decade 1990-1999 were: "); System.out.println(first.findRank(decade)); System.out.println(second.findRank(decade)); System.out.println(third.findRank(decade)); System.out.println(fourth.findRank(decade)); System.out.println(fifth.findRank(decade)); System.out.println(sixth.findRank(decade)); System.out.println(seventh.findRank(decade)); System.out.println(eighth.findRank(decade)); System.out.println(ninth.findRank(decade)); System.out.println(tenth.findRank(decade)); } if (!selection.equalsIgnoreCase("a") || !selection.equalsIgnoreCase("b") || !selection.equalsIgnoreCase("C") || !selection.equalsIgnoreCase("d")) ; { System.out.println("Invalid input. Try again"); } } while (!selection.equalsIgnoreCase("d")); if (selection.equalsIgnoreCase("d")) { } } public Static Name findName() { String fileName = "Names.txt"; Scanner inputStream = null; try { inputStream = new Scanner(new File(fileName)); } catch (FileNotFoundException e) { System.out.println("Error opening the file" + inputStream); System.exit(0); } String line; while (inputStream.hasNextLine()) { line = inputStream.nextLine(); String[] nameLine = line.split(" "); String babyName = nameLine[0]; int[] popularity; for (int k = 0; k < nameLine.length; k++) { popularity[k] = Integer.parseInt(nameLine[k + 1]); } if (this.equalsIgnoreCase(babyName)) { Name name = new Name(babyName, popularity); } else { System.out.print("Sorry that name was not found"); } } return name; } public Static String findRank(int decade) { String fileName = "Names.txt"; Scanner inputStream = null; try { inputStream = new Scanner(new File(fileName)); } catch (FileNotFoundException e) { System.out.println("Error opening the file" + inputStream); System.exit(0); } String top = ""; String line; while (inputStream.hasNextLine()) { line = inputStream.nextLine(); String[] nameLine = line.split(" "); String babyName = nameLine[0]; int[] popularity; for (int k = 0; k < nameLine.length; k++) { popularity[k] = Integer.parseInt(nameLine[k + 1]); } if (popularity[decade - 1] == Integer.parseInt(this)) { top = top + babyName + "(" + this + ")" + " "; } return top; } } }
这是编译错误
NameApp.java:126: ';' expected public Static Name findName() ^ NameApp.java:126: invalid method declaration; return type required public Static Name findName() ^ NameApp.java:161: ';' expected public Static String findRank(int decade) ^ NameApp.java:161: invalid method declaration; return type required public Static String findRank(int decade) ^ 4 errors
区分大小写可能是您的问题。 查看Stack Overflow问题Java是否区分大小写? 。
我建议改变static
的情况:
public static Name findName()
你的很多工作似乎都错了。 例如,字符串的声明。
这里有很多问题。 我强烈建议您重新阅读教程并与导师或TA坐下来敲定核心语法理解。
-
static
是一个关键字。 它区分大小写。 您必须将所有大写forms的static
更改为小写。 -
根据您的代码,没有任何名为
Name
类。 这将构成一个巨大的问题。 -
nameIn
是一个String
。 它没有名为findName
的方法。 -
int[] popularity
没有定义任何大小。 当您向此数组添加内容时,您将尝试取消引用null。 通过new int[nameLine.length]
适当地声明其大小。 -
这些行提供虚假信息; 我认为你的意思是将它们改为自然的数字排序,而不是让它一直向下?
System.out.println("1 - 1900-1909"); System.out.println("2 - 1910-1919"); System.out.println("1 - 1920-1929"); System.out.println("1 - 1930-1939"); System.out.println("1 - 1940-1949"); System.out.println("1 - 1950-1959"); System.out.println("1 - 1960-1969"); System.out.println("1 - 1970-1979"); System.out.println("1 - 1980-1989"); System.out.println("1 - 1990-1999"); System.out.println("1 - 2000-2005");
-
first
,second
,...
,tenth
都是String
类型。 他们没有findRank
方法。
我相信还有更多,但我会在这里停下来。 一旦你完成那些整理,你可能会处于主要位置以解决其余问题 。