Javatuples 简明教程

JavaTuples - Unit Class

Introduction

org.javatuples.Unit 类表示一个包含单个元素的元组。

The org.javatuples.Unit class represents a Tuple with single element.

Class declaration

以下是 org.javatuples.Unit 类的声明：

Following is the declaration for org.javatuples.Unit class −

public final class Unit<A>
   extends Tuple
      implements IValue0<A>

Class constructors

Sr.No.

Constructor & Description

Unit(A value0) This creates a Unit Tuple.

Class Methods

Sr.No.	Method & Description
1	Pair add(Unit tuple) This method returns a Pair tuple. Similarly other methods to add tuples are available e.g. add(Pair tuple) returns Triplet and upto add(Ennead tuple) returns Decade tuple.
2	Pair add(X0 value) This method add a value to the tuple and returns a Pair tuple. Similarly other methods to add values are available e.g. add(X0 value0, X1 value1) returns Triplet and so on upto add() with nine parameters.
3	Pair addAt0(Unit value) This method add a Unit tuple at index 0 and returns a Pair tuple. Similarly other methods to add tuples are available e.g. addAt0(Pair value) returns Triplet and so on upto addAt0(Ennead). Other similar method are addAt1(Unit value) which add a unit at index0 and have similar methods upto addAt1(Ennead).
4	Pair addAt0(X0 value) This method add a value at index 0 and returns a Pair tuple. Similarly other methods to add values are available e.g. addAt0(X0 value0, X1 value1) returns Triplet and so on upto addAt0() with nine parameters. Other similar method are addAt1(X0 value) which add a value at index0 and have similar methods upto addAt1() with nine parameters.
5	static <X> Unit<X> fromArray(X[] array) Create tuple from array.
6	static <X> Unit<X> fromCollection(Collection<X> collection) Create tuple from collection.
7	static <X> Unit<X> fromIterable(Iterable<X> iterable) Create tuple from iterable.
8	static <X> Unit<X> fromIterable(Iterable<X> iterable, int index) Create tuple from iterable, starting from the specified index.
9	int getSize() Return the size of the tuple.
10	A getValue0() Return the value of the tuple.
11	<X> Unit<X> setAt0(X value) Set the value of the tuple.
12	static <A> Unit<A> with(A value0) Create the tuple using given value.

Methods inherits

此类从以下类中继承方法：

This class inherits methods from the following classes −

org.javatuples.Tuple
Object

Example

我们来看一下 Unit 类的实际应用。我们将会看到如何使用各种方法。

Let’s see Unit Class in action. Here we’ll see how to use various methods.

在 C:>JavaTuples 中创建一个名为 TupleTester 的 Java 类文件。

Create a java class file named TupleTester in C:\>JavaTuples.

文件：TupleTester.java

File: TupleTester.java

package com.tutorialspoint;
import java.util.ArrayList;
import java.util.List;
import org.javatuples.Pair;
import org.javatuples.Unit;
public class TupleTester {
   public static void main(String args[]){
      Unit<Integer> unit = Unit.with(5);
      System.out.println(unit);
      boolean isPresent = unit.contains(5);
      System.out.println("5 is present: " + isPresent);
      List<Integer> list = new ArrayList<>();
      list.add(1);
      Pair<Integer, String> pair = unit.add("Test");
      System.out.println(pair);
      Integer value = unit.getValue0();
      System.out.println(value);
      Unit<Integer> unit1 = Unit.fromCollection(list);
      System.out.println(unit1);
   }
}

Verify the result

使用以下 javac 编译器编译类：

Compile the classes using javac compiler as follows −

C:\JavaTuples>javac -cp javatuples-1.2.jar ./com/tutorialspoint/TupleTester.java

现在运行 TupleTester 查看结果：

Now run the TupleTester to see the result −

C:\JavaTuples>java  -cp .;javatuples-1.2.jar com.tutorialspoint.TupleTester

Output

验证输出

Verify the Output

[5]
5 is present: true
[5, Test]
5
[1]