damiao/eladmin-system/src/main/java/me/zhengjie/base/pdf/CustomPageSplitter.java

package me.zhengjie.base.pdf;

import org.apache.pdfbox.multipdf.Splitter;

public class CustomPageSplitter extends Splitter {

	private int[] splitLength;

	/**
	 * This will tell the splitting algorithm where to split the pages. The default
	 * is 1, so every page will become a new document. If it was two then each
	 * document would contain 2 pages. If the source document had 5 pages it would
	 * split into 3 new documents, 2 documents containing 2 pages and 1 document
	 * containing one page.
	 *
	 * @param split The number of pages each split document should contain.
	 * @throws IllegalArgumentException if the page is smaller than one.
	 */
	public void setSplitAtPage(int... split) {
		if (split == null || split.length <= 0) {
			throw new IllegalArgumentException("Number of pages is smaller than one");
		}
		splitLength = split;
	}

	/**
	 * Check if it is necessary to create a new document. By default a split occurs
	 * at every page. If you wanted to split based on some complex logic then you
	 * could override this method. For example. <code>
	 * protected void splitAtPage()
	 * {
	 *     // will split at pages with prime numbers only
	 *     return isPrime(pageNumber);
	 * }
	 * </code>
	 * 
	 * @param pageNumber the 0-based page number to be checked as splitting page
	 * 
	 * @return true If a new document should be created.
	 */
	protected boolean splitAtPage(int pageNumber) {
		int result = 0;
		for (int i = 0; i < splitLength.length; i++) {
			result = splitLength[i] + result;
			if (result == pageNumber) {
				return true;
			}
		}
		return false;
	}
}