Quicksort for arraylist

public static ArrayList<Vehicle> quickSort(ArrayList<Vehicle> list)
{
    if (list.isEmpty()) 
        return list; // start with recursion base case
    ArrayList<Vehicle> sorted;  // this shall be the sorted list to return, no needd to initialise
    ArrayList<Vehicle> smaller = new ArrayList<Vehicle>(); // Vehicles smaller than pivot
    ArrayList<Vehicle> greater = new ArrayList<Vehicle>(); // Vehicles greater than pivot
    Vehicle pivot = list.get(0);  // first Vehicle in list, used as pivot
    int i;
    Vehicle j;     // Variable used for Vehicles in the loop
    for (i=1;i<list.size();i++)
    {
        j=list.get(i);
        if (j.compareTo(pivot)<0)   // make sure Vehicle has proper compareTo method 
            smaller.add(j);
        else
            greater.add(j);
    }
    smaller=quickSort(smaller);  // capitalise 's'
    greater=quickSort(greater);  // sort both halfs recursively
    smaller.add(pivot);          // add initial pivot to the end of the (now sorted) smaller Vehicles
    smaller.addAll(greater);     // add the (now sorted) greater Vehicles to the smaller ones (now smaller is essentially your sorted list)
    sorted = smaller;            // assign it to sorted; one could just as well do: return smaller

    return sorted;
}

Source: stackoverflow.com

Similar codes

0 vote177 views1 answer
Jasypt-spring-boot
Java
31 votes192 views6 answers
Java loops
Java
4 votes248 views2 answers
Java go troght loop object
Java
4 votes252 views1 answer
Find difference in days between two dates java
Java
0 vote191 views1 answer
Use regex in if statement java
Java
5 votes245 views3 answers
Failed to execute goal org.apache.maven.plugins:maven-surefire-plugin:2.19.1:test (default-test) on project
Java
1 vote182 views1 answer
Java print treemap
Java
1 vote188 views3 answers
Android studio json parser
Java
1 vote174 views1 answer
Convert string into unicode java
Java
1 vote191 views1 answer
This project uses AndroidX dependencies, but the 'android.useAndroidX' property is not enabled. Set this property to true in the gradle.properties file and retry.
Java