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String.replace() not replacing all occurrences

I have a very long string which looks similar to this.
355,356,357,358,359,360,361,382,363,364,365,366,360,361,363,366,360,361,363,366,360,361,363,366,360,361,363,366,360,361,363,366,360,361,363,366,360,361,363,366,368,369,313,370,371,372,373,374,375,376,377,378,379,380,381,382,382,382,382,382,382,383,384,385,380,381,382,382,382,382,382,386,387,388,389,380,381,382,382,382,382,382,382,390,391,380,381,382,382,382,382,382,392,393,394,395,396,397,398,399,....
When I tried using the following code to remove the number 382 from the string.
String str = "355,356,357,358,359,360,361,382,363,364,365,366,360,361,363,366,360,361,363,366,360,361,363,366,360,361,363,366,360,361,363,366,360,361,363,366,360,361,363,366,368,369,313,370,371,372,373,374,375,376,377,378,379,380,381,382,382,382,382,382,382,383,384,385,380,381,382,382,382,382,382,386,387,388,389,380,381,382,382,382,382,382,382,390,391,380,381,382,382,382,382,382,392,393,394,395,396,397,398,399,...."
str = str.replace(",382,", ",");
But it seems that not all occurrences are being replaced. The string which originally had above 3000 occurrences still was left with about 630 occurrences after replacing.
Is the capability of String.replace() limited? If so, is there a possible way of achieving what I need?

You need to replace the trailing comma as well (if one exists, which it won't if last in the list):
str = str.replaceAll("\\b382,?", "");
Note \b word boundary to prevent matching "-,1382,-".
The above will convert:
382,111,382,1382,222,382
to:
111,1382,222

I think the issue is your first argument to replace(), in particular the comma (,) before and after 382. If you have "382,382,383", you will only match the inner ",382," and leave the initial one behind. Try:
str.replace("382,", "");
Although this will fail to match "382" at the very end as it does not have a comma after it.
A full solution might entail two method calls thus:
str = str.replace("382", ""); // Remove all instances of 382
str.replaceAll(",,+", ","); // Compress all duplicates, triplicates, etc. of commas
This combines the two approaches:
str.replaceAll("382,?", ""); // Remove 382 and an optional comma after it.
Note: both of the last two approaches leave a trailing comma if 382 is at the end.

try this
str = str.replaceAll(",382,", ",");

Firstly, remove the preceding comma in your matching string. Then, remove duplicated commas by replacing commas with a single comma using java regular expression.
String input = "355,356,357,358,359,360,361,382,363,364,365,366,360,361,363,366,360,361,363,366,360,361,363,366,360,361,363,366,360,361,363,366,360,361,363,366,360,361,363,366,368,369,313,370,371,372,373,374,375,376,377,378,379,380,381,382,382,382,382,382,382,383,384,385,380,381,382,382,382,382,382,386,387,388,389,380,381,382,382,382,382,382,382,390,391,380,381,382,382,382,382,382,392,393,394,395,396,397,398,399";
String result = input.replace("382,", ","); // remove the preceding comma
String result2 = result.replaceAll("[,]+", ","); // replace duplicate commas
System.out.println(result2);

As dave already said, the problem is that your pattern overlaps. In the string "...,382,382,..." there are two occurrences of ",382,":
"...,382,382,..."
----- first occurrence
----- second occurrence
These two occurrences overlap at the comma, and thus Java can only replace one of them. When finding occurrences, it does not see yet what you replace the pattern with, and thus it doesn't see that new occurrence of ",382," is generated when replacing the first occurrence is replaced by the comma.
If your data is known not to contain numbers with more than 3 digits, then you might do:
str.replace("382,", "");
and then handle occurrences at the end as a special case. But if your data can contain big numbers, then "...,1382,..." will be replaced by "...,1,..." which probably is not what you want.
Here are two solutions that do not have the above problem:
First, simply repeat the replacement until no changes occur anymore:
String oldString = str;
str = str.replace(",382,", ",");
while (!str.equals(oldString)) {
oldString = str;
str = str.replace(",382,", ",");
}
After that, you will have to handle possible occurrences at the end of the string.
Second, if you have Java 8, you can do a little more work yourself and use Java streams:
str = Arrays.stream(str.split(","))
.filter(s -> !s.equals("382"))
.collect(Collectors.joining(","));
This first splits the string at ",", then filters out all strings which are equal to "382", and then concatenates the remaining strings again with "," in between.
(Both code snippets are untested.)

Traditional way:
String str = ",abc,null,null,0,0,7,8,9,10,11,12,13,14";
String newStr = "", word = "";
for (int i=0; i<str.length(); i++) {
if (str.charAt(i) == ',') {
if (word.equals("null") || word.equals("0"))
word = "";
newStr += word+",";
word = "";
} else {
word += str.charAt(i);
if (i == str.length()-1)
newStr += word;
}
}
System.out.println(newStr);
Output:
,abc,,,,,7,8,9,10,11,12,13,14

split string based on text qualifier regex java

I want to split a string based on text qualifier for example
"1","10411721","MikeTison","08/11/2009","21/11/2009","2800.00","002934538","051","New York","10411720-002",".\Images\b.jpg",".\RTF\b.rtf"
Qualifer="
Spliter = ,
I want to split string based on Spliter , but if Spliter comes inside qualifier " than ignore it and return string including Spliter .
Regular expression i am using is (?:|,)(\"(?:[^\"]+|\"\")*\"|[^,]*)
but this regular expression only returns commas,please help me in this perspective as i am new to regular expressions
please note that if we have newline characters in string ie \r\n than it should ignore newline character
"1","10411","Muis","a","21/11/2009","2800.06","0029683778","03005136851","Awan","10411720-001",".\Images\a.jpg",".\RTF\a.rtf"
"2","08/10/2009","07:32","Call","On-Net","030092343242342376543","Monk","00:00","1.500","0.000","10.000","0.200"
"2","08/10/2009","02:50","Call","Off-Net","030092343242342376543","Une","08:00","1.500","2.000","20.000","3.500"
"2","09/10/2009","03:55","SMS","On-Net","030092343242342376543","Mink","00:00","1.500","0.000","5.000","100.500"
"2","09/10/2009","12:30","Call","Off-Net","030092343242342376543","Zog","01:01","3.500","3.000","70.000","6.500"
"2","09/10/2009","09:11","Call","On-Net","030092343242342376543","Monk","02:30","2.00","2.000","90.000","4.000"

Probably easiest solution is not searching for place to split, but finding elements which you want to return. In your case these elements
starts "
ends with "
have no " inside.
So you try with something like
String data = "\"1\",\"10411721\",\"MikeTison\",\"08/11/2009\",\"21/11/2009\",\"2800.00\",\"002934538\",\"051\",\"New York\",\"10411720-002\",\".\\Images\\b.jpg\",\".\\RTF\\b.rtf\"";
Pattern p = Pattern.compile("\"([^\"]+)\"");
Matcher m = p.matcher(data);
while(m.find()){
System.out.println(m.group(1));
}
Output:
1
10411721
MikeTison
08/11/2009
21/11/2009
2800.00
002934538
051
New York
10411720-002
.\Images\b.jpg
.\RTF\b.rtf

You can split using this regex:
String[] arr = input.split( "(?=(([^\"]*\"){2})*[^\"]*$),+" );
This regex will split on commas if those are outside double quotes by using a lookahead to make sure there are even number of quotes after a comma.

Remove the first and the last character of the whole string. Then split with ","
String test = "\"1\",\"10411721\",\"MikeTison\",\"08/11/2009\",\"21/11/2009\",\"2800.00\",\"002934538\",\"051\",\"New York\",\"10411720-002\",\".\\Images\\b.jpg\",\".\\RTF\\b.rtf\"";
if (test.length() > 0)
test = test.substring(1, test.length()-1);
System.out.println(Arrays.toString(test.split("\",\"")));

This works even if you have new line character..try it out
String str="\"1\",\"10411721\",\"MikeTison\",\"08/11/2009\",\"21/11/2009\",\"2800.00\",\"002934538\",\"051\",\"New York\",\"10411720-002\",\".\\Images\\b.jpg\",\".\\RTF\\b.rtf\"";
System.out.println(Arrays.toString(str.split(",(?=([^\"]*\"[^\"]*\")*[^\"]*$)")));

How to convert the string into Array in Java

I have string as [arun, joseph, sachin, kavin]. I want to replace this text as ["arun", "joseph", "sachin", "kavin"]. All the values should be in double quotes.
I have tried to do this using replace method. But i could not accomplish. Can anyone help me to resolve this?

Your question is a bit unclear. Do you want to turn a string containing
[arun, joseph, sachin, kavin]
into this string
["arun", "joseph", "sachin", "kavin"]
or do you want to turn it into an actual array containing "arun", "joseph", "sachin" and "kavin"?
Regardless, this is pretty basic string manipulation. Here's what I suggest you try:
Use substring to get rid of the first and last character.
Use split to split the string on ", ".
If you want to add '"' before and after each component in this array, you can do
for (int i = 0; i < array.length; i++)
array[i] = '"' + array[i] + '"';

You could try this,
replace [, ] with an empty string.
Then do splitting according to the comma.
Strings parts[] = string.replaceAll("^\\[|\\]$", "").split("\\s*,\\s*");
^\\[|\\]$ matches the [, ] present at the start and at the end.
replaceAll function then replaces the matched brackets with an empty string.
Then by splitting the resultant string according to
\s* -> zero or more spaces
, -> comma
\s* -> zero or more spaces
will give you the desired output.

How to replace last letter to another letter in java using regular expression

i have seen to replace "," to "." by using ".$"|",$", but this logic is not working with alphabets.
i need to replace last letter of a word to another letter for all word in string containing EXAMPLE_TEST using java
this is my code
Pattern replace = Pattern.compile("n$");//here got the real problem
matcher2 = replace.matcher(EXAMPLE_TEST);
EXAMPLE_TEST=matcher2.replaceAll("k");
i also tried "//n$" ,"\n$" etc
Please help me to get the solution
input text=>njan ayman
output text=> njak aymak

Instead of the end of string $ anchor, use a word boundary \b
String s = "njan ayman";
s = s.replaceAll("n\\b", "k");
System.out.println(s); //=> "njak aymak"

You can use lookahead and group matching:
String EXAMPLE_TEST = "njan ayman";
s = EXAMPLE_TEST.replaceAll("(n)(?=\\s|$)", "k");
System.out.println("s = " + s); // prints: s = njak aymak
Explanation:
(n) - the matched word character
(?=\\s|$) - which is followed by a space or at the end of the line (lookahead)
The above is only an example! if you want to switch every comma with a period the middle line should be changed to:
s = s.replaceAll("(,)(?=\\s|$)", "\\.");

Here's how I would set it up:
(?=.\b)\w
Which in Java would need to be escaped as following:
(?=.\\b)\\w
It translates to something like "a character (\w) after (?=) any single character (.) at the end of a word (\b)".
String s = "njan ayman aowkdwo wdonwan. wadawd,.. wadwdawd;";
s = s.replaceAll("(?=.\\b)\\w", "");
System.out.println(s); //nja ayma aowkdw wdonwa. wadaw,.. wadwdaw;
This removes the last character of all words, but leaves following non-alphanumeric characters. You can specify only specific characters to remove/replace by changing the . to something else.
However, the other answers are perfectly good and might achieve exactly what you are looking for.

if (word.endsWith("char oldletter")) {
name = name.substring(0, name.length() - 1 "char newletter");
}

Parse and remove special characters in java regex

So we were looking at some of the other regex posts and we are having trouble removing a special case in one instance; the special character is in the beginning of the word.
We have the following line in our code:
String k = s.replaceAll("([a-z]+)[()?:!.,;]*", "$1");
where s is a singular word. For example, when parsing the sentence "(hi hi hi)" by tokenizing it, and then performing the replaceAll function on each token, we get an output of:
(hi
hi
hi
What are we missing in our regex?

You can use an easier approach - replace the characters that you do not want with spaces:
String k = s.replaceAll("[()?:!.,;]+", " ");

Position matters so you would need to match the excluded charcters before the capturing group also:
String k = s.replaceAll("[()?:!.,;]*([a-z]+)[()?:!.,;]*", "$1");

your replace just removed the "special chars" after the [a-z]+, that's why the ( before hi is left there.
If you know s is a single word
you could either:
String k = s.replaceAll("\\W*(\\w+)\\W*", "$1");
or
String k = s.replaceAll("\\W*", "");

This can be more simple
try this :
String oldString = "Hi There ##$ What is %#your name?##$##$ 0123$$";
System.out.println(oldString.replaceAll("[\\p{Punct}\\s\\d]+", " ");
output :
Hi There What is your name 0123
So it also accepts numeric.
.replaceAll("[\p{Punct}\s\d]+", " ");
will replace alll the Punctuations used which includes almost all the special characters.