Java Common class set interface and implementation method summary

Recently learned Map-reduce principle and map-reduce programming, Ushun with learning under Java programming, for Java commonly used data structure and class set, I summarize to mind diagram, easy to clarify the relationship between each other

Package Leiji;

Import java.util.ArrayList;

Import java.util.List;

Import java.util.Collection;

public class Arrylist {

public static void Main (String args[]) {

List arrlt=new ArrayList ();

Collection acoll=new ArrayList ();

Arrlt.add ("Hello");

Arrlt.add (0, "World");

System.out.println (ARRLT);

add element

Acoll.add ("Jerry");

Acoll.add ("Weibo");

Add Object

Arrlt.addall (Acoll);

Arrlt.addall (0,acoll);

System.out.println (ARRLT);

remove element

Arrlt.remove (1);

Arrlt.remove ("Weibo");

System.out.println (ARRLT);

     

Get element

for (int i=0;i<=arrlt.size () -1;i++) {

System.out.println (Arrlt.get (i));

}

// String a[] =new string[]{"1", "2"};

To change a collection to an array of objects

String Str[]=arrlt.toarray (New string[]{});  //

for (int i=0;i<=str.length-1;i++) {

System.out.println (Str[i]);

}

Object Obj[]=arrlt.toarray ();

for (int i=0;i<=obj.length-1;i++) {

System.out.println (String) obj[i]);

}

Determines whether the empty

System.out.println (Arrlt.isempty ());

Determine if an element is included

System.out.println (Arrlt.contains ("Hello")? " Hello is contains ":" Hello is not contains ");

Intercept sub-collections

List l=arrlt.sublist (1, 4);

for (int i=0;i

System.out.println (L.get (i));

}

System.out.println (L.indexof ("Hello"));

}

}

Java Common class set interface and implementation method summary