class
Static inner class example
This is an example of how to use a static inner class. We have set the example as described below:
- We have created a class,
ArAlgo
that contains a static inner classP
. - Class
P
has two double attributes and their getters. ArAlgo
class also has a static method,P min_max(double[] vals)
. The method gets a double array and for each value in the array and computes the minimum
and the maximum value in the array.- We create a new double array and fill it with random values, using
random()
API method of Math. Then we get a new instance ofP
class, usingmin_max(double[] vals)
method ofArAlgo
class, with the double array created above. We use the getters of theArAlgo
class to get the values of the two fields.
Let’s take a look at the code snippet that follows:
001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022 023 024 025 026 027 028 029 030 031 032 033 034 035 036 037 038 039 040 041 042 043 044 045 046 047 048 049 050 051 052 053 054 055 056 057 058 059 060 061 062 063 064 065 066 067 068 069 070 071 072 073 074 075 076 077 078 079 080 081 082 083 084 085 086 087 088 089 090 091 092 093 094 095 096 097 098 099 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 | package com.javacodegeeks.snippets.core; public class StaticInnerClass { public static void main(String[] args) { double [] num = new double [ 20 ]; for ( int i = 0 ; i < num.length; i++) { num[i] = 100 * Math.random(); } ArAlgo.P p = ArAlgo.min_max(num); System.out.println( "min = " + p.getF()); System.out.println( "max = " + p.getS()); } } class ArAlgo { /** * A pair of floating-point numbers */ public static class P { /** * Constructs a pair from two floating-point numbers */ private double f; private double s; public P( double a, double b) { f = a; s = b; } /** * Returns the first number of the pair */ public double getF() { return f; } /** * Returns the second number of the pair */ public double getS() { return s; } } /** * Computes both the minimum and the maximum of an array */ public static P min_max( double [] vals) { double min = Double.MAX_VALUE; double max = Double.MIN_VALUE; for ( double v : vals) { if (min > v) { min = v; } if (max < v) { max = v; } } return new P(min, max); } } |
Output:
min = 1.5117631236976625
max = 90.86550459529965
This was an example of static inner class in Java.