j
Java Arrays:
double[] myList; //preferred way or double myList[]; //works but not preferred way
Creating Arrays:
arrayRefVar=new dataType[arraySize]; dataType[] arrayRefVar=new dataType[arraySize]; Alternatively you can create arrays as follows: dataType[] arraRefVar={value0,value1,......,valueK};
The array elements are accessed throughthe index.Array indices are 0 based; that is, they start from 0 to arrayRefVar.length-1
double[] myList=new double[10];
public class TestArary { public static void main(String[] args){ double[] myList={1.9,2.9,3.4,3.5}; //Print all the array elements for(int i=0;i<myList.length;i++) { System.out.print(myList[i]+" "); } //Summing all elements double total=0; for(int i=0;i<myList.length;i++) { total=total+myList[i]; } System.out.println("Total is "+total); //Finding the largest element double max=myList[0]; for(int i=1;i<myList.length;i++) { if(myList[i]>max) { max=myList[i]; } System.out.println("Max is: "+ max); } } }
Output:
1.9 2.9 3.4 3.5 Total is 11.7 Max is: 2.9 Max is: 3.4 Max is: 3.5
foreach loops
public class TestArray{ public static void main(String[] args) { double[] myList={1.9,2.9,3.4,3.5}; //print all the array elements for(double element:MyList) { System.out.println(element); } } }
Output:
1.9 2.9 3.4 3.5
Passing Arrays to Methods:
public static void printArray(int[] array) { for(int i=0;i<array.length;i++) { System.out.println(array[i]+" "); } }
Returning an Array from a method:
public static int[] reverse(int[] list) { int[] result=new int[list.length]; for(int i=0;j=result.length-1;i<list.length;i++,j--) { result[j]=list[i]; } return result; }
The array class:
java.util.arrays for soritng and searching arrays,comparing and filling arrays.
public static int binarySearch(Object[] a,Object key)
public static boolean equals(long[] a1,long[] a2)
public static void fill(int[] a,int val)
public static void sort(Object[] a)