Java_去除字符串空格

 String ss = "    happy new year ";
 System.out.println(ss + "------" + ss.length());
 //"    happy new year ------16"
 System.out.println(ss.trim() + "------" + ss.trim().length());
 //"happy new year------14"
 System.out.println(ss.replaceAll(" ", "") + "------" + ss.replaceAll(" ", "").length());
 //"    happynewyear------13"
 System.out.println(ss.replaceAll("\\s*", "") + "------" + ss.replaceAll("\\s*", "").length());
 //"happynewyear------12"　　\s在正则里就表示空白符