Object Array with String Array elements-CodePudding

I have an array Object[] which contains elements that are arrays String[]. How can I get these elements as String[]?

Object[] arr = Files.lines(filePath)
    .map(n -> n.split(","))
    .filter(n -> n.length > 1)
    .toArray();
    
for (Object value : arr) {
    ....value[1]....    // compilation error here
}

CodePudding user response：

Compiler will not cast an Object into an array automatically, hence you're getting an error.

And instead of performing casting you can provide toArray() with a generator function to obtain an array String[][] (where each element is an array String[]) instead of generating an array Object[] as a result of the stream execution.

String[][] arr = Files.lines(filePath)
    .map(n -> n.split(","))
    .filter(n-> n.length > 1)
    .toArray(String[][]::new);

CodePudding user response：

You can convert the iterated item into a String array like this

import java.util.*;
import java.lang.*;
import java.io.*;

// The main method must be in a class named "Main".
class Main {
    public static void main(String[] args) {
        Object[] arr = new Object[] {
            new String[] {"a", "b", "c"},
            new String[] {"d", "e", "f"},
            new String[] {"g", "h", "i"}
        };
        for (Object value : arr) {
            System.out.println(((String[])value)[1]);
        }
    }
}

Fiddle: https://www.mycompiler.io/view/3AJo4kvla66