want to read a nested ArrayList from a text file.

[pompeez]

Hi,
I have a nested java ArrayList in a text file. I need to read that ArrayList in a Java program, and work with it. The problem is, whenever I am reading the file, I could only read the ArrayList as a String. Can anyone please help me to read the List in the file, as the same list in the java program?

Actually, I have created a java Arraylist in another program, and have copied the arraylist to a text file. The Arraylist is nested: (e.g. [a, b, [c, [d, e]]] ) Now, I need to read that ArrayList from the text in a java program and work with it. The problem I am facing is, I can read the ArrayList only as a string from the file. I am using :

" FileReader fr = new FileReader ("javaList.txt");
BufferedReader br = new BufferedReader (fr);"

Now, converting that string to a similar nested Arraylist is proving to be difficult for me. I don't know how to do it.

Thanks a lot!

[Phaelax]

Was the arraylist written to file as a serialized object or just plain text? If plain text, then what structure was it written? Just reverse the method you used for writing to read it back in.

[pompeez]

Hi, i read a python List and converted it to a Java list in Jython. This is the code in Jython :

input=open("pythonList.txt",'r')
fileList=input.readline()
input.close()

p = listquote.LineParser() // read the python list from the file as a list.
aList = p.feed(fileList)
anotherJavaList= java.util.LinkedList(aJavaList)

output = open('javaList.txt','w')
print >> output, anotherJavaList
output.close()

Now, I need to read that List from javaList.txt into a Java program, and work with that.
Thanks!

[Phaelax]

You may just have to save the list in a format you can easily parse so it can be recreated. You may want to consider saving the file in XML format.
Just as an example:

<container id="foo">
    <item>thing1</item>
    <item>thing2</item>
    <container id="stuff">
        <item>stuff</item>
    </container>
</container>
<container id="bar">
    <item>thing1</item>
</container>