com.github.akurilov.commons.io.collection.CircularArrayOutput Maven / Gradle / Ivy
package com.github.akurilov.commons.io.collection;
import java.io.IOException;
import java.util.List;
/**
An array output which may use fixed space for unlimited (circular) storing.
*/
public class CircularArrayOutput
extends ArrayOutput {
public CircularArrayOutput(final T[] items) {
super(items);
}
/**
@param item the item to put
@throws IOException if the destination collection fails to add the item
*/
@Override
public boolean put(final T item)
throws IOException {
if(i >= items.length) {
i = 0;
}
return super.put(item);
}
/**
Bulk circular put method
@param buffer the list of the items to put in a batch mode
@throws IOException if the destination collection fails to add the items
@return the size of the buffer to put
*/
@Override
public int put(final List buffer, final int from, final int to)
throws IOException {
//
int n = to - from;
if(buffer.size() > n) {
return put(buffer.subList(from, to), 0, n);
}
//
n = buffer.size();
if(n < items.length) {
// buffer may be placed entirely into the capacitor
final int limit = items.length - i; // how many free space is in the capacitor;
if(n > limit) {
// should remove some items from the beginning of the capacitor in order to place
// the buffer entirely
i = n - limit;
}
for(int j = from; j < to; j ++) {
items[i ++] = buffer.get(j);
}
} else {
// only a tail part of the buffer may be placed into the capacitor
i = 0; // discard all the items in the capacitor
for(int j = n - items.length; j < n; j ++) {
items[i ++] = buffer.get(j);
}
}
return n;
}
/**
@return the corresponding input
@throws IOException doesn't throw
*/
@Override
public CircularArrayInput getInput()
throws IOException {
return new CircularArrayInput<>(items);
}
@Override
public final String toString() {
return "circularArrayOutput<" + items.hashCode() + ">";
}
}