-------- Joiner guava tool string based on a given string is connected to the separator together

{class JoinerTest public 

    public static void main (String args []) { 

     //. 1, the set of strings list, in the form of a string into 
        List <String> the ArrayList list = new new <String> (); 
        List.add ( "XX"); 
        List.add ( "ZZ"); 
        List.add ( "dd"); 

        //Joiner.on ( ",") to obtain the object instance Joiner 
        Joiner Joiner = Joiner.on ( ","); 
        / /joiner.join(list) incoming set of operations, and to turn into a string format 
        System.out.println (joiner.join (List)); 
        // output: XX, ZZ, dd 

     // 2, the Iterator < T> list into a string 
        Iterator <string> = list.iterator (); 
        string str = Joiner.on ( "|") the Join (IT);. 
        System.out.println (str);
        // output: XX | ZZ | dd 

     //. 3, a plurality of strings connected
        . String str1 = Joiner.on ( ", ") join ( " small", "father", "mother", "grandfather", "grandmother"); 
        System.out.println (str1); 
        // output: small small, father, mother, grandfather, grandmother 

     // 4, the connection string list 
        StringBuilder builder = new StringBuilder ( "little cleverest"); 
        // return type StringBuilder 
        StringBuilder str2 = Joiner.on ( "," ) appendTo. (Builder, List); 
        System.out.println (str2); 
        // output: little behaved XX, ZZ, dd 

     //. 5, a null value is skipped connector 
        List.add (null); 
        List.add ( "small small "); 
        // skipNulls () on behalf of removing null 
        String str3 = Joiner.on (", ") skipNulls () the Join (List);.. 
        System.out.println (str3); 
        // output: xx, zz, dd,小小
Little 
     @ 6, replacing null value connector
        String str4=Joiner.on(",").useForNull("空").join(list); 
        System.out.println (str4); 
        // Output: xx, zz, dd, empty, little 

     // 7 , Map value pairs print 
        the Map <String, String> = new new Map the HashMap <> (); 
        map.put ( "key1", "VALUE1"); 
        map.put ( "key2", "value2"); 
        Map .put ( "key3", "value3"); 
        . Joiner.MapJoiner mapJoiner = Joiner.on ( ",") withKeyValueSeparator ( "="); 
        System.out.println (mapJoiner.join (Map)); 
        // output : = VALUE1 key1, key2 = value2, value3 = key3      

    //. 8, step the string to List <Long> set (first front Switch list <string>, with the back of the characteristic java8 List <string> Switch List < Long>)
    List<Long> list=Splitter.on("#").splitToList("111#222#333").stream().mapToLong(str->Long.parseLong(str)).boxed().distinct().collect(Collectors.toList());
} }