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Removal of comma in the end of a string android

i have problem how to , remove the comma in the of my output. I use replaceall but it doesnt remove the comma , this my code
public void onClick(View v) {
String space = "";
String foo = " ";
String foo1 = ",";
String sentences = null;
//Splitting the sentence into words
sentences = multiple.getText().toString().toLowerCase();
String[] splitwords = sentences.trim().split("\\s+");
for (String biyak : splitwords) {
foo = (foo + "'" + biyak + "'" + foo1);
foo.replaceAll(",$", " ");//foo.replaceAll();
wordtv.setText(foo);
My codes Output : 'Hello','world',
My desire output: 'Hello','world'

String instances are immutable. As a result, methods like replaceAll() do not modify the original string but instead return a modified copy of the string. So replace foo.replaceAll(...) with foo = foo.replaceAll(...).

you can use substring method of String class. or You can use deleteCharAt() method of StringBuilder or StringBuffer classStringBuffer sb=new StringBuffer(your_string);sb.deleteCharAt(sb.length()-1);

U can also use a if statement and traverse the whole string .
If a comma(,) is found replace it with a space(" ").

How to get the searched text in a string?

I want to get a text that it is a part of an string.For example: I have a string like "I am Vahid" and I want to get everything that it's after "am".
The result will be "Vahid"
How can I do it?

Try:
Example1
String[] separated = CurrentString.split("am");
separated[0]; // I am
separated[1]; // Vahid
Example2
StringTokenizer tokens = new StringTokenizer(CurrentString, "am");
String first = tokens.nextToken();// I am
String second = tokens.nextToken(); //Vahid

Try:
String text = "I am Vahid";
String after = "am";
int index = text.indexOf(after);
String result = "";
if(index != -1){
result = text.substring(index + after.length());
}
System.out.print(result);

Just use like this, call the method with your string.
public String trimString(String stringyouwanttoTrim)
{
if(stringyouwanttoTrim.contains("I am")
{
return stringyouwanttoTrim.split("I am")[1].trim();
}
else
{
return stringyouwanttoTrim;
}
}

If you prefer to split your sentence by blank space you could do like this :
String [] myStringElements = "I am Vahid".split(" ");
System.out.println("your name is " + myStringElements[myStringElements.length - 1]);

format a string with fill places

I have setup an edittext box and set the maxlength to 10. When I copy the edittext to a string myTitles. I need the myTiles to be 10 chars long and not dependent on what is entered in the edittext box.
myTitles[0] = TitlesEdit.getText().toString();
The edittext was filled with ABCD so I need to add 6 spaces or placeholders after the ABCD. I have seen other post with str_pad and substr without success
myTitles[0] = str_pad(strTest, 0, 10);
myTitles[0] = substr(strTest,0, 10);

Try something like
public static String newString(String str) {
for (int i = str.length(); i <= 10; i++)
str += "*";
return str;
}
This will return a String with * replaced for the empty ones.
So, for eg, if your String is abcde, then on calling newString() as below
myTitles[0] = newString("abcde");
will return abcde***** as the output.

String s = new String("abcde");
for(int i=s.length();i<10;i++){
s = s.concat("-");
}
Then output your string s.

Thank you Lal, I use " " to fill and it worked fine. here is my new code.
String strTest = TitlesEdit.getText().toString();
for (int i = strTest.length(); i <= 10; i++) {
strTest += " ";
}
Log.d("TAG", "String" + strTest);
myTitles[intLinenumber] = strTest;

How can I effectively replace one or more characters

I have a String separated by commas as follows
1,2,4,6,8,11,14,15,16,17,18
This string is generated upon user input. Suppose the user wants to remove any of the numbers, I have to rebuild the string without the specified number.
If the current string is:
1,2,4,6,8,11,14,15,16,17,18
User intents to remove 1, the final string has to be:
2,4,6,8,11,14,15,16,17,18
I tried to achieve this using the following code:
//String num will be the number to be removed
old = tv.getText().toString(); //old string
newString = old.replace(num+",",""); //will be the new string
This might be working sometimes but it is sure that it won't work for the above example I have shown, if I try to remove the 1, it also removes the last part of 11, because there also exists 1.

well you can use this. Its the most simplest approach i can think of:
//String num will be the number to be removed
old=","+tv.getText().toString()+",";//old string commas added to remove trailing entries
newString=old.replace(","+num+",",",");// will be the new string
newString=newString.substring(1,newString.length()-1); // removing the extra commas added
This would work for what you want to do. I have added a comma at the start and end of your string so that you can also remove the first and last entries too.

You can split the string first and check for the number where you append those value that is not equivalent to the number that will get deleted;
sample:
String formated = "1,2,4,6,8,11,14,15,16,17,18";
String []s = formated.split(",");
StringBuilder newS = new StringBuilder();
for(String s2 : s)
{
if(!s2.equals("1"))
newS.append(s2 + ",");
}
if(newS.length() >= 1)
newS.deleteCharAt(newS.length() - 1);
System.out.println(newS);
result:
2,4,6,8,11,14,15,16,17,18

static public String removeItemFromCommaDelimitedString(String str, String item)
{
StringBuilder builder = new StringBuilder();
int count = 0;
String [] splits = str.split(",");
for (String s : splits)
{
if (item.equals(s) == false)
{
if (count != 0)
{
builder.append(',');
}
builder.append(s);
count++;
}
}
return builder.toString();
}

String old = "1,2,4,6,8,11,14,15,16,17,18";
int num = 11;
String toRemove = "," + num + "," ;
String oldString = "," + old + ",";
int index = oldString.indexOf(toRemove);
System.out.println(index);
String newString = null;
if(index > old.length() - toRemove.length() + 1){
newString = old.substring(0, index - 1);
}else{
newString = old.substring(0, index) + old.substring(index + toRemove.length() -1 , old.length());
}
System.out.println(newString);

How to retrieve a specified data from a File?

I'm storing this data in a .dat file:
data = date + ": " + y + "L/100KM "+ " " + value1 + "dt "+ value2 + "KM\n";
Every line has different values of date,y,value1 and value2.
I want to retrieve variable value1 of every line. How to browse the file and extract this variable of all lines. I'm stucking in this problem in my project. Thanks for helping.
EDIT: Example:
I have this 3 datas stored in the file:
11/09: 5.8L/100KM 20dt 250KM
12/09: 6.4L/100KM 60dt 600KM
13/09: 7.5L/100KM 50dt 543KM
In that case, i want to retrieve 20dt, 60dt and 50dt.

Here's one suggestion using regular expressions:
String line = "12/09: 6.4L/100KM 60dt 600KM";
Pattern p = Pattern.compile("(\\d+)dt");
Matcher m = p.matcher(line);
if (m.find())
System.out.println(m.group(1)); // prints 60
If you have several lines to iterate over, you'd use for instance a new BufferedReader(new FileReader("youfile.dat")) and do something like
String line;
while ((line = br.nextLine()) != null) {
Matcher m = p.matcher(line);
if (m.find())
process(m.group(1));
}
You could also just use line.split(" ") and select the 3:rd element:
String line = "12/09: 6.4L/100KM 60dt 600KM";
String dtVal = line.split(" ")[2];
// Optional: Remove the "dt" part.
dtVal = dtVal.substring(0, dtVal.length() - 2);
System.out.println(dtVal);