Inserting String in a file using java

Question

I am trying to insert string value in an xml file , but I am not getting exactly how to insert using java.

textFieldChoose.setText(fileChooser.getSelectedFile().toString());

                    String str="";

                  final JFrame msgframe= new JFrame();
                  msgframe.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
                  str= textFieldChoose.getText();
                  JOptionPane.showMessageDialog(textFieldChoose, str);
                  ClassLoader classLoader = getClass().getClassLoader();
                  str= textFieldChoose.getText();

I can store the value in a string. I need to replace that value every time when whenever my application will pick another value in the string.

xml:-

?xml version="1.0" encoding="UTF-8"?>

<project name="org.world.rg" default="rg.init" basedir=".">

  <property name="dita.dir" location="${basedir}/../../.."/>

  <target name="rg.init" description="build PDF" depends="pdf"/>


  <target name="pdf" description="build PDF">
    <ant antfile="${dita.dir}/build.xml">
      <property name="args.input" location=""/>

I need to insert that string value in location =""/> . what are the possible ways?

score 0 · Answer 1 · edited May 23 '17 at 12:16

0

You can use an XPATH expression to update this element:

//project/target/ant/property ...

How to read XML using XPath in Java

edited May 23 '17 at 12:16

Community

1
1

answered Jan 16 '17 at 11:28

itstata

1,058
7
17

I am using this `XPath xPath = XPathFactory.newInstance().newXPath(); String expression = "/project/target[1]/ant/property/@location"; Node node = (Node) xPath.evaluate(expression, document, XPathConstants.NODE); node.setTextContent(str);` but facing exceptions . Can you instruct correct way to follow tags according to my xml. – Rohit Ghosh Jan 18 '17 at 07:35
The location attribute must be in brackets: //Parent[@id='1']/Children/child[@location] – itstata Jan 18 '17 at 07:40
Throwing lots of exceptions – Rohit Ghosh Jan 20 '17 at 04:51

score 0 · Answer 2 · answered Jan 16 '17 at 11:55

0

A simple way with java 8 API Files, but I do not think it's the best, it would be:

1) Read file 2) replace value 3) write file

byte[] fileContent = Files.readAllBytes(Paths.get("example.xml"));
String content = new String(fileContent)
                    .replace("location =\"\"", "location =\"" + str + "\"");
Files.write(Paths.get("example.xml"), xmlString.getBytes());

answered Jan 16 '17 at 11:55

Leonardo Ramos Duarte

292
3
10

Can you elaborate this parameter ? `location =\"\"", "location =\"" + str + "\"")` – Rohit Ghosh Jan 16 '17 at 12:32
I was trying to be simple, this is just the use of the replace method that the object String in java has. – Leonardo Ramos Duarte Jan 16 '17 at 12:50
Yes, I got you , but I need t understand this way of passing location. `(location =\?"\" ?? " , "location =\" ? " + str + "\"?")` – Rohit Ghosh Jan 16 '17 at 12:55
Are you in doubt why I'm escape the double quotes? – Leonardo Ramos Duarte Jan 16 '17 at 13:04
No , I know to pass char in that , I am in confusion with the to pass in the parameter. ("old char", "char") . But how exactly I am not getting that. – Rohit Ghosh Jan 17 '17 at 06:36
Can you mention this `location =\"\"", "location =\"" + str + "\"")` according to my xml file , because i am having lots of error in passing between the tags – Rohit Ghosh Jan 18 '17 at 07:32
You need insert string value in , right? – Leonardo Ramos Duarte Jan 18 '17 at 10:28
Yes , I just need to insert String value only in '"' (@location) – Rohit Ghosh Jan 18 '17 at 11:25
What are the mistakes? If location = "" is occurring more times, you can try to use a larger reference. – Leonardo Ramos Duarte Jan 18 '17 at 12:11
Not any mistake , I am unable to understand the node parsing. And input.arg location is not occurring more times , it is just updating/replacing the string (str) value. Just help me through the solution you had provided `location =\"\"", "location =\"" + str + "\"")` explain this through my xml file. – Rohit Ghosh Jan 18 '17 at 12:35

Inserting String in a file using java

2 Answers2