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Remove all <tag></tag> with text between

I'm trying to remove all text tagged like this (including the tags)
<tag>TEXT</tag>
from a String.
I have tried
.replaceAll("<tag>.+/(tag)*>", "")
or
.replaceAll("<tag>.*(tag)*>", "")
but neither works correctly and I can't replace the tagged text with ""

I don't know exactly what you want, so here are a few options:
String text = "ab<tag>xyz</tag>cd";
// Between
text.replaceAll("<tag>.+?<\/tag>", "<tag></tag>"); // ab<tag></tag>cd
// Everything
text.replaceAll("<tag>.+?<\/tag>", ""); // abcd
// Only tags
text.replaceAll("<\/?tag>", ""); // abxyzcd
EDIT:
The problem was the missing ? after the .+. The question mark only matches the first occurence, so it works when multiple tags are present which was the case.

Change to this ,
String nn1="<tag>TEXT</tag>";
nn1=nn1.replace("<tag>","");
nn1=nn1.replace("</tag>","");
OR
String nn1="<tag>TEXT</tag>";
nn1=nn1.replaceAll("<tag>","");
nn1=nn1.replaceAll("</tag>","");
Output : TEXT
I hope this helps you.

public static void removeTAG()
{
String str = "<tag>Your Long String</tag>";
for(int i=0;i<str.length();i++)
{
str = str.replace("<tag>", "");
str = str.replace("</tag>", "");
}
System.out.println(str);
}
Here what i did and output was as expected
Output Your Long String

You can use the below regular expression.
.replaceAll("<tag>.+?<\/tag>", "<tag></tag>");
This removes all the tags whether it's an HTML or an XML tag.

How do I recognize the initial white space/spaces in my edit text?

I am trying to recognize the initial spaces in my edit text, such that if a user enters " " (any number of spaces) ,it doesnt enable my done button.
So, far I have this code in placE:
String sendString = mSendText.getText().toString();
if(sendString.equals(" ")||sendString.isEmpty()||sendString ==null ){
//do nothing
}else {
//do my stuff
}
The thing is I want the else to work only when I have string with any characters in it as long as it is not JUST ALL whitespace in the beginning.
The code I have works for only 1 whitespace. I want to make it such that no matter how many number of whitespaces exist in the beginning it will remove them or not enable my done button as long as no characters show up.
For example :
This should go to the if loop: " "
This should go to the else loop: " Hello, it's me"
Any ideas?
Thanks!

Just replace equalsTo() to startsWith():
String sendString = mSendText.getText().toString();
if( (sendString == null) || (sendString.startsWith(" ")) || (sendString.isEmpty())){
//do nothing
}else{
//do my stuff
}
Perhaps, if you're interested only in relevant text, you can exclude white spaces in the beginning/ending just using trim()
String sendString = mSendText.getText().toString().trim();
if(sendString.isEmpty()) {
//do nothing
}else{
//do my stuff
}

Use trim() to delete odd spaces from begin and end of String.
String str = new String(" Welcome to Tutorialspoint.com ");
System.out.print("Return Value :" );
System.out.println(Str.trim() );
Returns Welcome to Tutorialspoint.com

I would remove all spaces then check to see if there is anything in the string after that.
String sendString = mSendText.getText().toString().replace(" ","");
if(sendString.isEmpty()){
// do nothing
}else{
// do something
}

android: check if the string not only white spaces

How can I check if a string contains anything other than whitespace?
This code didn't work:
String string = " \n\n\t\t ";
if(string.length()==0) doSomething();
since spaces and new lines have values.
Can anyone tell me how can I do it?
Note: minSDKVersion = 5
Regards :)

Try this:
if (string.trim().length() == 0) { /* all white space */ }
Alternatively, you can use a regular expression:
if (string.matches("\\w*")) { . . . }

try:
if (string == null || TextUtils.isEmpty(string.trim()) doSomething();

You can use trim to remove whitespace from both ends of the string. Then compare with the empty string.

Kotlin:
The below code takes the string, trims all of the letters down, and checks to see if the result is white space by using .isEmpty().
val str = " "
if (str.trim().isEmpty()) {
// white space only
} else {
// this string has actual characters/letters in it
}

Try: it works
if (txt.getText().toString().trim().matches(" ")){
Toast.makeText(getApplicationContext(), "You did not select any text"
, Toast.LENGTH_LONG).show();
}
else{
}

Program seems to be ignoring lines of code

I need help with this function.
I know that the if statement recognizes my input because it affects the program elsewhere, but I'm not sure what's going on because this particular Log doesn't display anything even in adb logcat.
Other Log statements in the same class file that this function is from display just fine, and the value update does seem to be changing ("show all" blanks it for some reason but I can figure that out after I get the log to work.)
I am unsure how to search for this problem because it is very specific and I have no idea what causes it (probably something simple that I didn't think of, though.)
void command(String input)
{
//do stuff here
//update = whatever
if(input.equalsIgnoreCase("show all"))
{
update=printAllRooms();
Log.i(input, update);
}
else update=input; //just for testing, will delete later
}
the printAllRooms function:
public String printAllRooms() //for debug purposes
{
String result = "";
for (Iterator<Room> iterator = rooms.iterator(); iterator.hasNext();) {
Room current = iterator.next();
result = result + current.toString()+"\n";
Log.i("printallrooms", current.toString());
}
return result;
}

A note on using Log.
The first argument sent to Log is typically a fixed string indicating the name of the class you are in.
So at the top of your class you might define:
private static final String TAG = "MyClassName";
Then you would use TAG for your log statements in that class.
Log.i(TAG, "My input was: " + input + " Update was: " + update;
To put it mildly, your function looks quite odd. Set a breakpoint at your Log statement, run the debugger and then inspect the variable value contained in update. Most likely, printAllRooms() is not doing what you think.

If the iterator doesn't work for you, try using the For-Each loop:
for (Room r : rooms) {
result = result + r.toString()+"\n";
Log.i("printallrooms", r.toString());
}

IfElse or regex

Which one of these would be the best way to do this when you have very long IfElse?
if (text.contains("text"))
{
// do the thing
}
else if (text.contains("foo"))
{
// do the thing
}
else if (text.contains("bar"))
{
// do the thing
}else ...
Or
if (text.contains("text") || text.contains("foo") || ...)
{
// do the thing
}
Or maybe
Pattern pattern = Pattern.compile("(text)|(foo)|(bar)|...");
Matcher matcher = pattern.matcher(text);
if(matcher.find())
{
// do the thing
}
And I mean ONLY when you have to check a lot of these. Thanks!

I would personally use a set as I think it is easier to read and the contains will be efficient in O(1):
Set<String> keywords = new HashSet<String>();
keywords.add("text");
keywords.add("foo");
keywords.add("bar");
if(keywords.contains(text)) {
//do your thing
}
And if you like it compact, you can also write:
Set<String> keywords = new HashSet<String>(Arrays.asList("text", "foo", "bar"));
if(keywords.contains(text)) {
//do your thing
}
And finally, if you always use the same list, you can make keywords private static final instead of recreating it each time you run the method.
EDIT
Following a comment, it is true that what is above is equivalent to using a condition with text.equals("xxx"), not text.contains("xxx"). If you really meant to use contains, then you would have to iterate over the set and test each string, but it becomes an O(n) operation:
for (String key : keywords) {
if (text.contains(key)) {
//do your stuff
break;
}
}

Usually long If else statements are replaced with case statements, but this is not always possible. If I where to recommend, I would go for the second option, option 1 will give you a bunch of If else if else statements which do the same thing while for the third case, regular expressions tend to grow pretty large pretty fast.
Again depending on how much alot is, it could eventually be better to just throw all your strings in a data structure and iterate over it to see if the element is in it.

String[] storage = {
"text",
"foo",
"bar",
"more text"
};
for(int i=0; i < storage.length(); i++){
//Do Something
}
Does this help?