在编写采用数组列表和整数作为输入的方法的标头时，会遇到多个错误。
我尝试了几种不同的方法来编写方法的标题。主体很好，可以给我我想要的东西，但是我不能得到标题/调用名称（我不知道您称方法的第一行）不会抛出错误
/**
* Creates Arraylist "list" using prompt user for the input and output file path and sets the file name for the output file to
* p01-runs.txt
*
*/
Scanner scan = new Scanner(System.in);
System.out.println("Please enter the path to your source file: ");
String inPath = scan.nextLine(); // sets inPath to user supplied path
System.out.println("Please enter the path for your source file: ");
String outPath = scan.nextLine() + "p01-runs.txt"; // sets outPath to user supplied input path
ArrayList<Integer> listRunCount = new ArrayList<Integer>();
ArrayList<Integer> list = new ArrayList<Integer>();
/**
* Reads data from input file and populates array with integers.
*/
FileReader fileReader = new FileReader(inPath);
BufferedReader bufferedReader = new BufferedReader(fileReader);
// file writing buffer
PrintWriter printWriter = new PrintWriter(outPath);
System.out.println("Reading file...");
/**
* Reads lines from the file, removes spaces in the line converts the string to
* an integer and adds the integer to the array
*/
File file = new File(inPath);
Scanner in = new Scanner(file);
String temp=null;
while (in.hasNextLine()) {
temp = in.nextLine();
temp = temp.replaceAll("\\s","");
int num = Integer.parseInt(temp);
list.add(num);
}
listRunCount.findRuns(list, RUN_UP);
//********************************************************************************************************
public ArrayList<Integer> findRuns(ArrayList<Integer> list, int RUN_UP){
returns listRunCount;
}
错误消息
Multiple markers at this line
- Syntax error on token "int", delete this token
- Syntax error, insert ";" to complete LocalVariableDeclarationStatement
- Integer cannot be resolved to a variable
- ArrayList cannot be resolved to a variable
- Syntax error, insert ";" to complete LocalVariableDeclarationStatement
- Illegal modifier for parameter findRuns; only final is permitted
- Syntax error, insert ") Expression" to complete CastExpression
- Syntax error on token "findRuns", = expected after this token
- Syntax error, insert "VariableDeclarators" to complete
LocalVariableDeclaration
- Syntax error, insert ";" to complete Statement
答案 0 :(得分：0)
这类事情消除了对静电的需求。如果您从静态方法 main（）中运行代码，则所有在main（）内部调用或引用的类方法，成员变量等也必须声明为 static 。通过执行：
public class Main {
public static void main(String[] args) {
new Main().run();
}
}
消除了对静态的需要。我认为要正确执行此操作，还应将args []参数传递给类中的 run（）方法：
public class Main {
public static void main(String[] args) {
new Main().run(args);
}
private void run(String[] args) {
// You project code here
}
}
这样，也可以从 run（）方法中处理传递给应用程序的任何命令行参数。您会发现大多数人不会将方法名称 run 用于此类事情，因为 run（）是与线程的运行更相关的方法名称。像 startApp（）这样的名称更合适。
public class Main {
public static void main(String[] args) {
new Main().startApp(args);
}
private void startApp(String[] args) {
// You project code here
}
}
牢记所有这些，您的代码可能看起来像这样：
public class Main {
public static void main(String[] args) {
new Main().run(args);
}
private void run(String[] args) {
String runCountFileCreated = createListRunCount();
if (!runCountFileCreated.equals("") {
System.out.println(The count file created was: " + runCountFileCreated);
}
else {
System.out.println(A count file was NOT created!);
}
}
/**
* Creates an ArrayList "list" using prompts for the input and output file
* paths and sets the file name for the output (destination) file to an
* incremental format of p01-runs.txt, p02-runs.txt, p03-runs.txt, etc. If
* p01 exists then the file name is incremented to p02, etc. The file name
* is incremented until it is determined that the file name does not exist.
*
* @return (String) The path and file name of the generated destination
* file.
*/
public String createListRunCount() {
String ls = System.lineSeparator();
File file = null;
Scanner scan = new Scanner(System.in);
// Get the source file path from User...
String sourceFile = "";
while (sourceFile.equals("")) {
System.out.print("Please enter the path to your source file." + ls
+ "Enter nothing to cancel this process:" + ls
+ "Source File Path: --> ");
sourceFile = scan.nextLine().trim(); // User Input
/* If nothing was entered (just the enter key was hit)
then exit this method. */
if (sourceFile.equals("")) {
System.out.println("Process CANCELED!");
return "";
}
// See if the supplied file exists...
file = new File(sourceFile);
if (!file.exists()) {
System.out.println("The supplied file Path/Name can not be found!." + ls
+ "[" + sourceFile + "]" + ls + "Please try again...");
sourceFile = "";
}
}
String destinationFile = "";
while (destinationFile.equals("")) {
System.out.print(ls + "Please enter the path to folder where data will be saved." + ls
+ "If the supplied folder path does not exist then an attempt" + ls
+ "will be made to automatically created it. DO NOT supply a" + ls
+ "file name. Enter nothing to cancel this process:" + ls
+ "Destination Folder Path: --> ");
String destinationPath = scan.nextLine();
if (destinationPath.equals("")) {
System.out.println("Process CANCELED!");
return "";
}
// Does supplied path exist. If not then create it...
File fldr = new File(destinationPath);
if (fldr.exists() && fldr.isDirectory()) {
/* Supplied folder exists. Now establish a new incremental file name.
Get the list of files already contained within this folder that
start with p and a number (ex: p01-..., p02--..., p03--..., etc)
*/
String[] files = fldr.list(); // Get a list of files in the supplied folder.
// Are there any files in the supplied folder?
if (files.length > 0) {
//Yes, so process them...
List<String> pFiles = new ArrayList<>();
for (String fileNameString : files) {
if (fileNameString.matches("^p\\d+\\-runs\\.txt$")) {
pFiles.add(fileNameString);
}
}
// Get the largest p file increment number
int largestPnumber = 0;
for (int i = 0; i < pFiles.size(); i++) {
int fileNumber = Integer.parseInt(pFiles.get(i).split("-")[0].replace("p", ""));
if (fileNumber > largestPnumber) {
largestPnumber = fileNumber;
}
}
largestPnumber++; // Increment the largest p file number by 1
// Create the new file name...
String fileName = String.format("p%02d-runs.txt", largestPnumber);
//Create the new destination File path and name string
destinationFile = fldr.getAbsolutePath() + "\\" + fileName;
}
else {
// No, so let's start with p01-runs.txt
destinationFile = fldr.getAbsolutePath() + "\\p01-runs.txt";
}
}
else {
// Supplied folder does not exist so create it.
// User Confirmation of folder creation...
JFrame iFrame = new JFrame();
iFrame.setAlwaysOnTop(true);
iFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
iFrame.setLocationRelativeTo(null);
int res = JOptionPane.showConfirmDialog(iFrame, "The supplied storage folder does not exist!"
+ ls + "Do you want to create it?", "Create Folder?", JOptionPane.YES_NO_OPTION);
iFrame.dispose();
if (res != 0) {
destinationFile = "";
continue;
}
try {
fldr.mkdirs();
}
catch (Exception ex) {
// Error in folder creation...
System.out.println(ls + "createListRunCount() Method Error! Unable to create path!" + ls
+ "[" + fldr.getAbsolutePath() + "]" + ls + "Please try again..." + ls);
destinationFile = "";
continue;
}
destinationFile = fldr.getAbsolutePath() + "\\p01-runs.txt";
}
}
ArrayList<Integer> list = new ArrayList<>();
/* Prepare for writing to the destination file.
Try With Resourses is use here to auto-close
the writer. */
try (PrintWriter printWriter = new PrintWriter(destinationFile)) {
System.out.println(ls + "Reading file...");
/**
* Reads lines from the file, removes spaces in the line converts
* the string to an integer and adds the integer to the List.
*/
String temp = null;
/* Prepare for writing to the destination file.
Try With Resourses is use here to auto-close
the reader. */
try (Scanner reader = new Scanner(file)) {
while (reader.hasNextLine()) {
temp = reader.nextLine().replaceAll("\\s+", "");
/* Make sure the line isn't blank and that the
line actually contains no alpha characters.
The regular expression: "\\d+" is used for
this with the String#matches() method. */
if (temp.equals("") || !temp.matches("\\d+")) {
continue;
}
int num = Integer.parseInt(temp);
list.add(num);
}
// PLACE YOUR WRITER PROCESSING CODE HERE
}
catch (FileNotFoundException ex) {
Logger.getLogger("createListRunCount() Method Error!").log(Level.SEVERE, null, ex);
}
}
catch (FileNotFoundException ex) {
Logger.getLogger("createListRunCount() Method Error!").log(Level.SEVERE, null, ex);
}
/* return the path and file name of the
destination file auto-created. */
return destinationFile;
}
}