Develop Reference

How to split the string from a file?

I have a simple text file with information in it called logindata.txt . And it looks like this:
username1:password1:username2:password2
The plan is to split the line at the " : " symbol.
This is my code so far...
(...)
final StringBuilder text = new StringBuilder();
try {
BufferedReader br = new BufferedReader(new FileReader(file));
try {
String line;
while ((line = br.readLine()) != null) {
text.append(text);
//stuff over here ?
}
} catch (IOException e) {
e.printStackTrace();
}
} catch (FileNotFoundException e) {
e.printStackTrace();
}
This works perfectly fine if my file only has one word in it.
But I want to use the file to store all the usernames and passwords (This is only for learning purposes I know it's a bit stupid) in the end like this:
(...)
login_button.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
if (username.getText().toString().equals(text.toString()) && password.getText().toString().equals(text.toString()))
//Stuff happening here if the username & password is correct...
(...)
I'm completely stuck and have tried many examples for splitting a string and none seem to work.

In your case I would like to use a Map<Username, Password> with Pattern like this :
String line = "username1:password1:username2:password2";
Map<String, String> userPass = new HashMap<>();
Pattern pattern = Pattern.compile("([^:]+):([^:]+)");
Matcher matcher = pattern.matcher(line);
while (matcher.find()) {
userPass.put(matcher.group(1), matcher.group(2));
}
System.out.println(userPass);
Outputs
{username2=password2, username1=password1}
If you want to check if the user exist or not, you can use :
String username = "username1";
String password = "password1";
if(userPass.containsKey(username) && userPass.get(username).equals(password)){
//User exist
}
In case you values can be repeated you can use another structure or create a new Object which hold username and password, instead of a map

a general code would be for splitting text would be
class Main {
public static void main(String[] args) {
String text = "username1:password1:username2:password2";
String[] vals = text.split(":");
for (String temp: vals){
System.out.println(temp);
}
}
}

To split a String in java, you could use String#split(string regex).
In your case, after have the file read into a String, you could put all pairs of username/password into a HashMap for lookup.
String text = "username1:password1:username2:password2"; // you would read it from the file
String[] segments = text.split(":"); // split the string with ":"
Map<String, String> userPassMap = new HashMap<>(); // initialize the map to store user info
for (int i = 0; i < segments.length; i+=2) {
userPassMap.put(segments[i], segments[i+1]);
}
And for your login validation
login_button.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
String user = username.getText().toString().trim(); // trim() to get rid of heading and trailing empty spaces
String pass = password.getText().toString().trim();
if (userPassMap.containsKey(user) && userPassMap.get(user).equals(pass)) {
//Stuff happening here if the username & password is correct...
}
(...)

Apply regex on url string

I have a url like this,
http://abc-xyz.com/AppName/service?id=1234&isStudent&stream&shouldUpdateRecord=Y&courseType
I want to apply a regex before making a rest call to a 3rd party system. That regex should remove all the keys without a value. i.e from this given url, my regex should remove "&isStudent", "&stream" and "&courseType" and I should be left with,
http://abc-xyz.com/AppName/service?id=1234&shouldUpdateRecord=Y
Any pointers?

I can't do it in one regex, because the number of key-only parameters is variable. But I can do it with a short program like this
public class Playground {
public static void main(String[] args) {
String testInput = "http://abc-xyz.com/AppName/service?id=1234&isStudent&stream&shouldUpdateRecord=Y&courseType";
String[] tokens = testInput.split("\\?");
String urlPrefix = tokens[0];
String paramString = tokens[1];
String[] params = paramString.split("&");
StringBuilder sb = new StringBuilder();
sb.append(urlPrefix + "?");
String keyValueRegex = "(\\w+)=(\\w+)";
String amp = ""; // first time special
for (String param : params) {
if (param.matches(keyValueRegex)) {
sb.append(amp + param);
amp = "&"; // second time and onwards
}
}
System.out.println(sb.toString());
}
}
The output of this program is this:
http://abc-xyz.com/AppName/service?id=1234&shouldUpdateRecord=Y

How to set jsp variable in java script array?

Hi I am trying to set jsp variable into a javascript array. I tried, but I am not able to achieve this when I run my code. I do not get my output, I only see a blank screen.
Here is my code:
value.jsp
<script>
<%
URL url;
ArrayList<String> list1 = new ArrayList<String>();
ArrayList<String> list2 = new ArrayList<String>();
List commodity = null;
List pric = null;
int c = 0;
int p = 0;
try {
// get URL content
String a = "http://122.160.81.37:8080/mandic/commoditywise?c=paddy";
url = new URL(a);
URLConnection conn = url.openConnection();
// open the stream and put it into BufferedReader
BufferedReader br = new BufferedReader(
new InputStreamReader(conn.getInputStream()));
StringBuffer sb = new StringBuffer();
String inputLine;
while ((inputLine = br.readLine()) != null)
{
System.out.println(inputLine);
// sb.append(inputLine);
String s=inputLine.replace("|", "\n");
s = s.replace("~"," ");
StringTokenizer str = new StringTokenizer(s);
while(str.hasMoreTokens())
{
String mandi = str.nextElement().toString();
String price = str.nextElement().toString();
list1.add(mandi);
list2.add(price);
}
}
commodity = list1.subList(0,10);
pric = list2.subList(0,10);
for (c = 0,p = 0; c < commodity.size()&& p<pric.size(); c++,p++)
{
String x = (String)commodity.get(c);
String y = (String)pric.get(p);
//out.println(y);
//out.println(x);}
%>
jQuery(function ($) {
var roles = [];
roles.push(<%= x%>)
roles.push(<%= y%>)
<%
}
%>
var counter = 0;
var $role = $('#role')
//repeat the passed function at the specified interval - it is in milliseconds
setInterval(function () {
//display the role and increment the counter to point to next role
$role.text(roles[counter++]);
//if it is the last role in the array point back to the first item
if (counter >= roles.length) {
counter = 0;
}
}, 400)
});
</script>
<%
br.close();
//System.out.println(sb);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
%>
How can I achieve my desired output?

When you output to JS from JSP, you have to make sure your output is valid JS.
Your current output will output a string with no quotes, which the JS interpreter will treat as JS code and not strings or arrays as you want.
In addition, you are producing 10 copies of the JS
jQuery(function ($) {
var roles = [];
roles.push(<%= x%>)
roles.push(<%= y%>)
and that function is never closed.
I would look for a decent JSON output library. That would simplify your life quite a bit here.

It looks like you are clearing the roles variable var roles = []; with each pass of the loop.
You might want to consider not posting the entire file, but pairing the example down to just the part you need help with.
You could also put the array into a JSON object and parse that in your javascript. That might be a cleaner implementation.

try enclosing the scriptlets with quotes like roles.push("<%= x%>") and also check the array initialization.

Splitting a String without spaces

I have the following string which is generated by an external program (OpenVAS) and returned to my program successfully as a string.
<create_target_response id="b4c8de55-94d8-4e08-b20e-955f97a714f1" status_text="OK, resource created" status="201"></create_target_response>
I am trying to split the string to give me the "b4c8d....14f1" without the inverted commas. I have tried all sorts of escape methods and keep getting the else method "String does not contain a Target ID". I have tried removing the IF statement checking for the string, but continue to have the same issue. The goal is to get my id string into jTextField6. String Lob contains the full string as above.
if (Lob.contains("id=\"")){
// put the split here
String[] parts = Lob.split("id=\"");
String cut1 = parts[1];
String[] part2 = cut1.split("\"");
String TaskFinal = part2[0];
jTextField6.setText(TaskFinal);
}
else {
throw new IllegalArgumentException("String does not contain a Target ID");
}
} catch (IOException e) {
e.printStackTrace();
}
It seems I only need to escape the " and not the = (Java kicks up an error if i do)
Thanks in advance
EDIT: Code as it stands now using jSoup lib - The 'id' string won't display. Any ideas?
Thanks
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
String TargIP = jTextField1.getText(); // Get IP Address
String TargName = jTextField5.getText(); // Get Target Name
String Vag = "8d32ad99-ac84-4fdc-b196-2b379f861def";
String Lob = "";
final String dosCommand = "cmd /c omp -u admin -w admin --xml=\"<create_target><name>" + TargName + "</name><hosts>" + TargIP + "</hosts></create_target>\"";
3</comment><config id='daba56c8-73ec-11df-a475-002264764cea'/><target id='" + Vag + "'/></create_task>\"";
final String location = "C:\\";
try {
final Process process = Runtime.getRuntime().exec(
dosCommand + " " + location);
final InputStream in = process.getInputStream();
int ch;
while((ch = in.read()) != -1) {
System.out.print((char)ch);
Lob = String.valueOf((char)ch);
jTextArea2.append(Lob);
}
} catch (IOException e) {
e.printStackTrace();
}
String id = Jsoup.parse(Lob).getAllElements().attr("id");
System.out.println(id); // This doesn't output?
}

Split on the basis of ". You can get all the key values.
String str = "<create_target_response id=\"b4c8de55-94d8-4e08-b20e-955f97a714f1\" status_text=\"OK, resource created\" status=\"201\"></create_target_response>";
String[] tokens = str.split("\\\"");
System.out.println(tokens[1]);
System.out.println(tokens[5]);
output:
b4c8de55-94d8-4e08-b20e-955f97a714f1
201

This will get you your job id more easily:
int idStart = Lob.indexOf("id=")+("id=\"").length();
System.out.println(Lob.substring(idStart,Lob.indexOf("\"",idStart)));

Everyone's telling you to use an XML parser (and they're right) but noone's showing you how.
Here goes:
String lob = ...
Using Jsoup from http://jsoup.org, actually an HTML parser but also handles XML neatly:
String id = Jsoup.parse(lob).getAllElements().attr("id");
// b4c8de55-94d8-4e08-b20e-955f97a714f1
With built-in Java XML APIs, less concise but no addtional libraries:
Document dom = DocumentBuilderFactory.newInstance().newDocumentBuilder()
.parse(new InputSource(new StringReader(lob)));
String id = dom.getDocumentElement().getAttribute("id");
// b4c8de55-94d8-4e08-b20e-955f97a714f1

This is a lot simpler than you're making it, to my mind. First, split on space, then check if an = is present. If it is, split on the =, and finally remove the " from the second token.
The tricky bit is the spaces inside of the "". This will require some regular expressions, which you can work out from this question.
Example
String input; // Assume this contains the whole string.
String pattern; // Have fun working out the regex.
String[] values = input.split(pattern);
for(String value : values)
{
if(value.contains("=")) {
String[] pair = value.split("=");
String key = pair[0];
String value = pair[1].replaceAll("\"");
// Do something with the values.
}
}
Advantage of my approach
Is that provided the input follows the format of key="value" key="value", you can parse anything that comes through, rather than hard coding the name of the attributes.
And if this is XML..
Then use an XML parser. There is a good (awesome) answer that explains why you shouldn't be using Stringmanipulation to parse XML/HTML. Here is the answer.

You can use a regex to extract what is needed; what is more, it looks like the value of id is a UUID. Therefore:
private static final Pattern PATTERN
= Pattern.compile("\\bid=\"([^\"]+)\"");
// In code...
public String getId(final String input)
{
final Matcher m = PATTERN.matcher(input);
if (!m.find())
throw new IllegalArgumentException("String does not contain a Target ID");
final String uuid = m.group(1);
try {
UUID.fromString(uuid);
} catch (IllegalArgumentException ignored) {
throw new IllegalArgumentException("String does not contain a Target ID");
}
return uuid;
}

Extract jsp page from the whole URL

I am using request.getHeader("Referer") to get the previous page URL from where I came. But I am getting here the complete URL for example http://hostname/name/myPage.jsp?param=7. Is there any way to extract myPage.jsp?param=7from the whole URL? Or I need to process the string?I just need myPage.jsp?param=7.

You can simply reconstruct URL by using this function. Use only the things you need from this function.
public static String getUrl(HttpServletRequest req) {
String scheme = req.getScheme(); // http
String serverName = req.getServerName(); // hostname.com
int serverPort = req.getServerPort(); // 80
String contextPath = req.getContextPath(); // /mywebapp
String servletPath = req.getServletPath(); // /servlet/MyServlet
String pathInfo = req.getPathInfo(); // /a/b;c=123
String queryString = req.getQueryString(); // d=789
// Reconstruct original requesting URL
String url = scheme+"://"+serverName+":"+serverPort+contextPath+servletPath;
if (pathInfo != null) {
url += pathInfo;
}
if (queryString != null) {
url += "?"+queryString;
}
return url;
}
or If this function does not fulfil your need, then you can always use String manipulation:
public static String extractFileName(String path) {
if (path == null) {
return null;
}
String newpath = path.replace('\\', '/');
int start = newpath.lastIndexOf("/");
if (start == -1) {
start = 0;
} else {
start = start + 1;
}
String pageName = newpath.substring(start, newpath.length());
return pageName;
}
Pass in /sub/dir/path.html returns path.html
Hope this helps. :)

class URI - http://docs.oracle.com/javase/7/docs/api/java/net/URI.html
just build a new URI instance with the string you have (http://hostname/name/myPage.jsp?param=7) and then you can access parts. what you want is probably getPath()+getQuery()

Pattern p = Pattern.compile("[a-zA-Z]+.jsp.*");
Matcher m = p.matcher("http://hostname/name/myPage.jsp?param=7");
if(m.find())
{
System.out.println(m.group());
}