java集合转字符串

// 方法一：

public String listToString1(List list, char separator) {

StringBuilder sb = new StringBuilder();

for (int i = 0; i < list.size(); i++) {

sb.append(list.get(i)).append(separator);

}

return sb.toString().substring(0, sb.toString().length() - 1);

}

// 方法二：

public String listToString2(List list, char separator) {

StringBuilder sb = new StringBuilder();

for (int i = 0; i < list.size(); i++) {

if (i == list.size() - 1) {

sb.append(list.get(i));

} else {

sb.append(list.get(i));

sb.append(separator);

}

}

return sb.toString();

}

// 方法三：

public String listToString3(List list, char separator) {

StringBuilder sb = new StringBui