Guava’s Joiner class provides various methods to handle joining operations on string, objects, etc. This class provides advanced functionality for the join operation.
Declaration: Following is the declaration for com.google.common.base.Joiner class :
@GwtCompatible public class Joiner extends Object
The following table gives a brief summary of the methods provided by Guava’s Joiner class:
Example:
// Java code to show implementation of // Guava's Joiner class's method import com.google.common.base.Joiner;
import java.util.*;
class GFG {
// Driver's code
public static void main(String[] args)
{
// Creating a string array
String[] arr = { "one" , "two" , "three" , "four" };
System.out.println( "Original Array: "
+ Arrays.toString(arr));
// Use Joiner to combine all elements.
// ... Specify delimiter in on method.
// The last part of the Joiner statement, join,
// can receive an Iterable (like an ArrayList) or
// an Object array. It returns a String.
String result = Joiner.on( "..." )
.join(arr);
System.out.println( "Joined String: "
+ result);
}
} |
Output:
Original Array: [one, two, three, four] Joined String: one...two...three...four
Some more methods provided by Guava’s Joiner class are:
Example:
// Java code to show implementation of // Guava's Joiner class's method import com.google.common.base.Joiner;
import java.util.*;
class GFG {
// Driver's code
public static void main(String[] args)
{
// Creating a string array
String[] arr = { "one" , "two" , null ,
"four" , null , "five" };
System.out.println( "Original Array: "
+ Arrays.toString(arr));
// Unlike the standard join method, we can
// filter elements with a Joiner. With skipNulls,
// null elements in an array or Iterable are removed.
// Often null elements are not needed.
// $$ Specify delimiter in on method.
// The last part of the Joiner statement, join,
// can receive an Iterable (like an ArrayList) or
// an Object array. It returns a String.
String result = Joiner.on( '+' )
.skipNulls()
.join(arr);
System.out.println( "Joined String: "
+ result);
}
} |
Output:
Original Array: [one, two, null, four, null, five] Joined String: one+two+four+five
Reference: Google Guava Joiner Class