I'm new to Java/Android development. I need to get the specific values from my string array.
String PictureTest[] = {"a.jpg","b.png","c.txt", "d.wav", "e.tga"};
This array is diffrent every time. I need to get all values which contain .jpg, .png, .tga and form a new array with them.
System.out.println(Arrays.toString(PictureResult));
//It prints "a.jpg, b.png, e.tga"
UPD: Thanks everyone for this quick and useful responses!
Use a for loop to iterate through the elements in PictureTest[] and check if each of them contains() the extensions. Use an ArrayList or List to store the values because the size of an array cannot be modified.
String PictureTest[] = {"a.jpg","b.png","c.txt", "d.wav", "e.tga"};
ArrayList<String> PictureResult = new ArrayList<String>;
for(String item : PictureTest) {
if(item.contains(".jpg") || item.contains(".png") || item.contains(".tga") {
PictureResult.add(item);
}
}
Edit: If you only need to check the file extension at the end, you can use endsWith() instead of contains().
In a simple way you can iterate over the original array and search for your pattern:
List<String> pictureResult = new ArrayList<String>();
for(String picture : PictureTest) {
//use something like contains or a regex, for example
if (picture.contains(".jpg"))
pictureResult.add(picture);
//etc...
}
You get the idea...
If you are using Java 8, you can use Predicates to filter your list. Something like this:
public class PredicateTester {
public static void main(String args[]) {
String PictureTest[] = {"a.jpg","b.png","c.txt", "d.wav", "e.tga"};
List<String> filteredList = filterStrings(PictureTest, filter());
filteredList.forEach(System.out::println);
}
public static Predicate<String> filter() {
return p -> p.endsWith(".jpg") || p.endsWith(".png") || p.endsWith(".tga");
}
public static List<String> filterStrings (String[] fileNames, Predicate<String> predicate) {
return Arrays.asList(fileNames).stream().filter( predicate ).collect(Collectors.<String>toList());
}
}
