字符串"1\n2\\n3\n4\\n5"，匹配\\n，以下两种方式等价，第二种不容易出错，不用考虑字符串带来的问题，下载jar包。

package com.test;

import org.apache.commons.lang3.StringUtils;

public class Test12 {

	public static void main(String[] args) {
		String ss1 = "1\n2\\n3\n4\\n5";
		System.out.println("本身字符串:");
		System.out.println(ss1);
		String[] array = ss1.split("\\\\n");
		for (int i = 0; i < array.length; i++) {
			System.out.println("第" + (i + 1) + "个:" + array[i] + "  ");
		}
		System.out.println();
		String[] array1 = StringUtils.splitByWholeSeparator(ss1,"\\n");

		for (int i = 0; i < array1.length; i++) {
			System.out.println("第" + (i + 1) + "个:" + array1[i] + "  ");
		}

	}

}