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)