Java-在txt文件中绘制线条阅读点

Question

I'm trying to understand how Java and in particular Swing work, so I made an application for drawing freehand lines on a JPanel. Then with the Save button I can memorize some informations (when user began and ended drawing the line, which points make the line etc.).

I save informations this way:

EDIT I remomed useless stuff and simply put a space between different informations..

line 04:54:34:365 04:54:35:167 [java.awt.Point[x=249,y=114], java.awt.Point[x=249,y=114], java.awt.Point[x=207,y=87], java.awt.Point[x=207,y=87]]

This is an example of a line; can you suggest me how to parse the file to draw the lines back to the JPanel? I think it should work like "for every line, go after 'points' word and take the data and draw it". Is it the correct way to do it? I've already managed to read and write from/to the file, so the problem resides in taking only that part of the line and give it as an input to the drawing function.

This is the way I read from the file (.txt):

List<String> lines = Files.readAllLines(Paths.get(file.getPath()), Charset.forName("UTF-8"));

Thank you!

Answer 1

I would do something similar to AnubianNoob's suggestion but with each drawn "line", even made up of many points, on each line in your text file. Even if you don't wish to do that, it would be easiest to simply print out only the numbers and not the whole object.

After creating two lines, maybe text file looks like:

249 114 207 87 230 110
115 240 90 210 112 245

Now you can read all lines like you do already, and then split each line by the space (or whatever character you want to put between values)

//for each line in lines
String[] values = line.split(" ");
//Note we are adding 2 to i in each loop, because the 2nd value will be y value
for (int i = 0; i < values.length; i+=2)
{
    //Now just recreate the points
    //values[i] = x, values[i+1] = y
}