java String that contains the substring containing characters

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String father="Welcome you to come here";
String child ="you";

1. The use indexOf String class () method returns a value! = - 1 comprising, returns the specified first occurrence of the string index within this string. 2. String.matches method comprising determining whether the substring, attention regular expression metacharacters escape 3.StringUtils.contains determines whether the packet contains a character org.apache.commons.lang.StringUtils classes provided 4..String method public boolean contains (CharSequence s) reference:. [. 1] http://codingstandards.iteye.com/blog/1181490

Reproduced in: https: //my.oschina.net/itfanr/blog/195672