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Split or tokenise a java String using a substring as delimiter

How to split or tokenise a String in java not based on regex but based on a substring?
String str = "{A={111={i=[a,b,c],ii=[e,f]}, 222={iii=[a,e]}}, B={333={i= [b,c]}}};
Now I want to tokenise or split the string based on substring "}}," and not regex "}},".

Although the String.split(String regex) function specifies that it takes a regular expression as a parameter, that does not stop you from escaping any special characters and splitting on a literal string.
To escape special characters in a regular expression, you can make use of the Pattern.quote(String s) function, or you can escape the individual characters using backslashes \\:
String escapedStr = Pattern.quote("}},");
String alternativeEscapedStr = "\\}\\},";
For the example you have provided however, you shouldn't need to escape anything:
String str = "{A={111={i=[a,b,c],ii=[e,f]}, 222={iii=[a,e]}}, B={333={i= [b,c]}}}";
String[] splitStr = str.split(Pattern.quote("}},"));
System.out.println(Arrays.toString(splitStr));
String[] splitStr2 = str.split("}},");
System.out.println(Arrays.toString(splitStr2));
Output:
[{A={111={i=[a,b,c],ii=[e,f]}, 222={iii=[a,e], B={333={i= [b,c]}}}]
[{A={111={i=[a,b,c],ii=[e,f]}, 222={iii=[a,e], B={333={i= [b,c]}}}]

String str = "{A={111={i=[a,b,c],ii=[e,f]}, 222={iii=[a,e]}}, B={333={i= [b,c]}}}";
String[] split = str.trim().split("}},");
Arrays.stream(split).forEach(s-> System.out.println(s));

split string based on comma delimiter

what is wrong in the following code?
String selectedCountriesStr = countries.replaceAll("[", "").replaceAll("]", "").trim();
String[] selectedCountriesArr = selectedCountriesStr.split(",");
Input String [10000,20000,304050,766666]
Getting error java.util.regex.PatternSyntaxException: Unclosed character class near index 0

You have to escape square brackets because replaceAll() interprets the first argument as a regular expression:
replaceAll("\\[", "")
^^
because, as the error message tells you, the are used for character classes in a regex. Double backslashes are necessary, because "\[" would be an invalid escape sequence. Since the backslash is escaped, the regex engine only receives one backslash.
Also, you can use
replace("[", "")
it will also replace all occurrences of the given CharSequence as is.
You can read more about it in JavaDoc.

Brackets are regex metacharacters, you need to prefix them with a backslash:
.replaceAll("\\[", "").replaceAll("\\]", "")
Also, since this is a simple string substitution, you'd better use .replace():
.replace("[", "").replace("]", "")

String str = "hi,hello,abc,example,problems";
String[] splits = str.split(",");
System.out.println("splits.size: " + splits.length);
for(String asset: splits){
System.out.println(asset);
}
Split function will easily split your string like this

Java: String split acting weird

public String getPriceString() {
String priceString = "45.0";
String[] priceStringArray = priceString.split(".");
return priceStringArray.length + "";
}
Why does this give me a 0, zero? Shouldn't this be 2?

The argument to split() is a regular expression, and dot has a special meaning in regular expressions (it matches any character).
Try priceString.split("[.]");

You need to escape . like that
String[] priceStringArray = priceString.split("\\.");
split takes regular expression as a parameter and . means any character.
http://docs.oracle.com/javase/6/docs/api/java/util/regex/Pattern.html#sum

escape . with backslash like \\.. . is a regex metacharacter for anything. you will have to escape it with \\. in order to make it treat as a normal character
String priceString = "45.0";
String[] priceStringArray = priceString.split("\\.");

String.split takes a regular expression pattern. You're passing in . which means you want to split on any character.
You could use "\\." as the pattern to split on - but personally I'd use Guava instead:
private static final Splitter DOT_SPLITTER = Splitter.on('.');
...
(If you're not already using Guava, you'll find loads of goodies in there.)

You need to escape . as \\. because . has special meaning in regex.
String priceString = "45.0";
String[] priceStringArray = priceString.split("\\.");
return priceStringArray.length + "";

Use String[] priceStringArray = priceString.split("\\.");
You will have to use escape sequence.

How can I split a string by two delimiters?

I know that you can split your string using myString.split("something"). But I do not know how I can split a string by two delimiters.
Example:
mySring = "abc==abc++abc==bc++abc";
I need something like this:
myString.split("==|++")
What is its regularExpression?

Use this :
myString.split("(==)|(\\+\\+)")

How I would do it if I had to split using two substrings:
String mainString = "This is a dummy string with both_spaces_and_underscores!"
String delimiter1 = " ";
String delimiter2 = "_";
mainString = mainString.replaceAll(delimiter2, delimiter1);
String[] split_string = mainString.split(delimiter1);
Replace all instances of second delimiter with first and split with first.
Note: using replaceAll allows you to use regexp for delimiter2. So, you should actually replace all matches of delimiter2 with some string that matches delimiter1's regexp.

You can use this
mySring = "abc==abc++abc==bc++abc";
String[] splitString = myString.split("\\W+");
Regular expression \W+ ---> it will split the string based upon non-word character.

Try this
String str = "aa==bb++cc";
String[] split = str.split("={2}|\\+{2}");
System.out.println(Arrays.toString(split));
The answer is an array of
[aa, bb, cc]
The {2} matches two characters of the proceding character. That is either = or + (escaped)
The | matches either side
I am escaping the \ in java so the regex is actually ={2}|\+{2}

How to split the string using '^' this special character in java?

I want to split the following string "Good^Evening" i used split option it is not split the value. please help me.
This is what I've been trying:
String Val = "Good^Evening";
String[] valArray = Val.Split("^");

I'm assuming you did something like:
String[] parts = str.split("^");
That doesn't work because the argument to split is actually a regular expression, where ^ has a special meaning. Try this instead:
String[] parts = str.split("\\^");
The \\ is really equivalent to a single \ (the first \ is required as a Java escape sequence in string literals). It is then a special character in regular expressions which means "use the next character literally, don't interpret its special meaning".

The regex you should use is "\^" which you write as "\\^" as a Java String literal; i.e.
String[] parts = "Good^Evening".split("\\^");
The regex needs a '\' escape because the caret character ('^') is a meta-character in the regex language. The 2nd '\' escape is needed because '\' is an escape in a String literal.

try this
String str = "Good^Evening";
String newStr = str.replaceAll("[^]+", "");