Java文本输入：如何忽略以某些字符开头的行？

Question

I basically want to ignore certain lines with characters in them, like if there's a line

// hello, i'm bill

I want to ignore that line while reading it because it contains the character "//". How can I do that? I tried method skip(), but it gives me errors.

public String[] OpenFile() throws IOException {

  FileReader reader = new FileReader(path);
  BufferedReader textReader = new BufferedReader(reader);

  int numberOfLines = readLines();
  String[] textData = new String[numberOfLines];
  int i;

  for (i=0; i<numberOfLines; i++) {
      textData[i] = textReader.readLine();
  }

  // close the line-by-line reader and return the data
  textReader.close();
  return textData;
}

int readLines() throws IOException {
  FileReader reader = new FileReader(path);
  BufferedReader textReader = new BufferedReader(reader);
  String line;
  int numberOfLines = 0;

  while ((line = textReader.readLine()) != null) { 
    // I tried this:
    if (line.contains("//")) {
      line.skip();  
    }
    numberOfLines++;       
  }    
  reader.close();  
  return numberOfLines;
}

Update: HERE's MY MAIN METHOD:

try{
 ReadFile files = new ReadFile(file.getPath());
 String[] anyLines = files.OpenFile();
 }

Answer 1

while ((line = textReader.readLine()) != null) {

    // I tried this:
    if (line.contains("//")) {
      continue;
    }

    numberOfLines++;

}

note that continue might seem a bit goto like and be prone to critique

---

edit here's what you are after (note this doesn't need the countLines method)

public String[] OpenFile() throws IOException {
   FileReader reader = new FileReader(path);
   BufferedReader textReader = new BufferedReader(reader);

   List<String> textData = new LinkedList<String>();//linked list to avoid realloc
   String line;
   while ((line = textReader.readLine()) != null) {
       if (!line.contains("//")) textData.add(line);
   }

   // close the line-by-line reader and return the data
   textReader.close();
   return textData.toArray(new String[textData.size()]);
}

Answer 2

As Andrew Thompson points out, it would be best to read the file line by line into an ArrayList. Pseudo-Code:

 For Each Line In File
   If LineIsValid()
     AddLineToArrayList()
 Next

UPDATE to fix your actual code:

public String[] OpenFile() throws IOException {

  FileReader reader = new FileReader(path);
  BufferedReader textReader = new BufferedReader(reader);

  int numberOfLines = readLines();
  String[] textData = new String[numberOfLines];
  int BufferIndex = 0;
  String line;

  while ((line = textReader.readLine()) != null) {
    if (line.trim().startsWith("//")) {
      // Don't inject current line into buffer
    }else{
       textData[BufferIndex] = textReader.readLine();
       BufferIndex = BufferIndex + 1;
    }      
  }

  // close the line-by-line reader and return the data
  textReader.close();
  return textData;
}

In your ReadLines() Function:

while ((line = textReader.readLine()) != null) {
    if (line.trim().startsWith("//")) {
      // do nothing
    }else{
      numberOfLines++;
    }      
}

Basically, you're on the right track.

Note : You may be interested in the startsWith() string function