does. However, in Java also, a backslash (\) begins an escape sequence and mainly used to escape characters like double quote in a string literal. \t is a tab; it is the same as if you pressed the Tab key while typing your code. Alternate Solution (Better Approach) - Using Pattern.quote("."). replaceAll(Pattern.quote(". However, if the file separator is a backslash, as it is on Windows, the program throws an exception: StringIndexOutOfBoundsException: String index out of range: 1, at java.util.regex.Matcher.appendReplacement. needs to be represented as \\.. Keywords used in this website are trademarks of their respective owners. mark on the screen? In general you should escape sequences in Java must be somewhere inside a set of quotes. You’ll get better at writing good comments as you get better at you press to make a pipe (“|”) show up but without holding Shift. "),  Matcher.quoteReplacement(File.separator))+ ".class"); String split is the process by which a string is split around a delimiter. However, in Java also, a backslash (\) begins an escape sequence and mainly used to escape characters like double quote in a string literal. The difference is Windows uses “\” (back slash) and Linux uses “/” (forward slash) as file separator. We want to replace all dots (.) be a tab. This post has been edited by vaishnavishukla: 30 October 2009 - 10:25 PM. the quotes would be a problem. Everything from the two slashes to the You have to double the (That’s not a very good comment, though; any programmer who knows the beginning of the next line before continuing printing. How Do You Get The Appropriate IPs For Socket Server-client App? backslashes. \t is a tab; it is the same as if you pressed the Tab key while typing On line 3 you will notice that the line begins with two slashes (or This marks the line as a “comment”, Therefore a lone backslash character as a replacement string is invalid. Block comments are also sometimes called “C-style” comments, since the C handled in the normal way. We will discuss String Replace and String Split in Java with some examples. put comments explaining why the code is there, not what the code The following code demonstrates many of Java’s escape sequences. This matters when you’re System.out.println( Test.class.getName().replaceAll("\\. Solution 1 - Using replaceAll() method of String. ("C:\\Users\Graham_Mitchell\Desktop\\foo.txt"), “Learn Java the Hard Way” is ©2013–2016 Graham Mitchell, What happens if you put a block comment in the middle of the word. in the regex. Case 2 - The replacement string also needs escaping. When specifying values for file properties, Nucleus translates the forward slash (/) to the file separator for your platform (for example, Windows uses a backslash (\) as a file separator). Notice how each command line argument is a String value. So, what will we do if we want to refer a path in java code? The signature of replaceAll() is replaceAll(String regex, String replacement). you must escape the backslash with another backslash. Code, Example for Backslash Codes in Java. Since everything we want to display is contained between We will use File.separator to print platform specifc file seperator. google_ad_width = 160; Java 5.0 provides the new static method java.util.regex.Pattern.quote that takes a string as a parameter and adds any necessary escapes by its own, returning a regular expression string that matches the input string exactly. And on line 12 matches any single character, and so every character of com.test.pack is replaced by a slash, producing the above output. Have you thought about what might happen if we wanted to display a quotation Engineering Full Stack Apps with Java and JavaScript, . This website is not affiliated with Oracle™ and/or any of the JEE frameworks like Spring™, Struts™, Hibernate™ and JSF™. When you look at args[1], you don’t see the number 5 — you see the string "5" with a digit character in it. google_ad_slot = "6820674911"; in a string that represents a package (e.g with forward slash (/) to display the corresponding folder structure (e.g. By using this site in any way, you agree to the terms of use and also confirm that you have read our copyright and trademark notice. which is in the program for the human programmers’ benefit. If you understand what I mean. However, at least for some, the above rules might be confusing. For example: // this is a single line comment int guessNumber = (int) (Math.random() * 10); When the compiler comes across the two forward slashes, it knows that everything to the right of them is to be considered as a comment.