Java FAQ Java String substitution method uses the

The following code:

public class Example020 {public static void main (string[] args) {String separator = File.separator; String clazzname = Example020.class.getName (); String rs1 = Clazzname.replace (".", separator); Method 1String rs2 = Clazzname.replaceall ("\ \", "\\\\");//method 2String Rs3 = Clazzname.replaceall (Pattern.quote ("."), Matcher.quotereplacement (separator));//Method 3system.out.println ("Class name =" + Clazzname); System.out.println ("rs1=" + rs1); System.out.println ("rs2=" + rs2); System.out.println ("rs3=" + Rs3);}}

Analysis Description:

The above code is three ways to replace Java strings. Java provides two methods for string substitution since version 1.5: Replace and ReplaceAll. Both methods have the same functionality and are able to replace all the characters in the string that need to be replaced (although the naming is confusing). The difference is that theparameters passed in by the Replace method are the characters to be replaced and the substituted character, and the ReplaceAll pass in a regular representation of the character to be replaced and the replacement.

Using ReplaceAll, the second parameter passed in the "\ \" unfriendly error hint exception in thread "main" java.lang.StringIndexOutOfBoundsException:String index Out of Range:1at java.lang.String.charAt (string.java:658) at Java.util.regex.Matcher.appendReplacement (Matcher.java : 762) at Java.util.regex.Matcher.replaceAll (matcher.java:906) at Java.lang.String.replaceAll (string.java:2162) at Cn.itape.java.disabuse.Example020.main (example020.java:13)

• In Method 3, from 1.5, Java provides two methods, the string directly into the form of regular expressions, directly use, to avoid the need to join in Method 2 to escape, reduce the likelihood of errors.
  

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Source code Address: Https://github.com/rocwinger/java-disabuse

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Java FAQ Java String substitution method uses the