I have 3 generic arrays which all have a pre-determined size of 25. For example, if its only 5 actual values in the array, it will display those 5, than the next 20 as null. I dont want to display any null values. Do I edit something in the toString? My toString is
public String toString(){
return Arrays.toString(container);
}
Container being an array object created from a constructor function. Here is what my output looks like..
The Arrays.toString() methods all produce a representation of the whole array. If that's not what you want, then you need to choose a different approach. For example, you might do something like this:
String result = Arrays.stream(container)
.filter(Objects::nonNull)
.map(Objects::toString)
.collect(Collectors.joining(",", "[", "]"));
In the following, I suppose your container is something like Something []container.
Pre-java 8 using StringBuilder:
public String toString(){
StringBuilder s = new StringBuilder();
for (Something i : container) if (i!=null) s.append(i.toString()+",");
return s.toString();
}
Post-java 8 using streams:
public String toString(){
return Arrays.stream(container)
.filter(Objects::nonNull)
.map(Object::toString)
.collect(Collectors.joining(","));
}
Assuming you use java8 or later:
Arrays.toString(Arrays.stream(container).filter(i->i!=null).collect(Collectors.toList()));
Another solution with java8 stream:
MyType[] array = Arrays.stream(originalArray)
.filter(Objects::nonNull)
.toArray(MyType[]::new);
System.out.println(Arrays.toString(array));
Object[]?ArrayListinstead of array or keep a top pointer to the first vacant slot so you know which part of the array to print. Then there are a number of options for printing.