如何将list中字符串采用逗号拼接呢?

list字符串逗号拼接的实现思路

方式1：
   借助工具类
      如:StringUtils.join

方式2:
   借助for循环进行拼接

 public class TestClass {
private static String[] array = {"java265.com", "java我最爱好", "这是最好的java网站"};
private static String str;

public static void main(String[] args) {
	List<String> list = new ArrayList<>();
	for (int i = 0; i < array.length; i++) {
		list.add(array[i]);
	}
	/**
	 *
	 * 将集合用字符串，逗号隔开拼接
	 * */
	//第一种方法(灵活，可以用逗号隔开，用|线隔开)
	str = StringUtils.join(list, ",");
	System.out.println("第一种方法" + str);
	//第二种方法
	str = listToString1(list);
	System.out.println("第二种方法" + str);
	//第三种方法(灵活，可以用逗号隔开，用|线隔开)
	str = listToString2(list, ',');
	System.out.println("第三种方法" + str);
	//第四种方法
	str = listToString3(list, ",");
	System.out.println("第四种方法" + str);
	Separator separator=new Separator(",");
	//第五种方法
	str = listToString4(list, separator );
	System.out.println("第五种方法"+str);
}
public static String listToString1(List<String> list) {
	StringBuilder sb = new StringBuilder();
	if (list != null && list.size() > 0) {
		for (int i = 0; i < list.size(); i++) {
			if (i < list.size() - 1) {
				sb.append(list.get(i) + ",");
			} else {
				sb.append(list.get(i));
			}
		}
	}
	return sb.toString();
}
public static String listToString2(List list, char separator) {
	StringBuilder sb = new StringBuilder();
	for (int i = 0; i < list.size(); i++) {
		sb.append(list.get(i)).append(separator);
	}
	return list.isEmpty() ? "" : sb.toString().substring(0, sb.toString().length() - 1);
}
public static String listToString3(List list, String separator) {
	StringBuilder sb = new StringBuilder();
	for (int i = 0; i < list.size(); i++) {
		sb.append(list.get(i));
		if (i < list.size() - 1) {
			sb.append(separator);
		}
	}
	return sb.toString();
}
public static class Separator {
	private String next = "";
	private String separator;
	public Separator(String separator) {
		this.separator = separator;
	}
	public String get() {
		String result = next;
		next = separator;
		return result;
	}
}
public static String listToString4(List<String> list, Separator separator) {
	StringBuilder sb = new StringBuilder();
	for (String s : list) {
		if (s != null && !"".equals(s)) {
			sb.append(separator.get()).append(s);
		}
	}
	return sb.toString();
}