1 /**
2 * <p>list操作的工具类</p>
3 */
4 public class ListUtil {
5 /**
6 * 过滤掉list里面才重复项
7 *
8 * @param list
9 * @return List
10 */
11 public static List<String> filterRepeat(List<String> list){
12 int length = list.size();
13 for(int i = 0;i < length - 1;i++){
14 String temp = list.get(i).toString();
15 for(int j = i + 1;j < length;j++){
16 if(temp.equals(list.get(j))){
17 list.remove(j);
18 j--;
19 length--;
20 }
21 }
22 }
23 return list;
24 }
25
26 /**
27 * 判断list是否null或者长度为零，常用于从数据库取对象后的判断
28 *
29 * @param list
30 * @return true:空 false：非空
31 */
32 public static boolean isNull(List list) {
33 if (null == list || list.size() == 0) {
34 return true;
35 } else {
36 return false;
37 }
38 }
39
40 /**
41 * list 是否有存在字符串value的值
42 *
43 * @param list
44 * 链表
45 * @param value
46 * 值
47 * @return true: 存在，false：不存在
48 */
49 public static boolean valueIsExit(List list, String value) {
50 for (int i = 0; i < list.size(); i++) {
51 if (value.equals(list.get(i).toString())) {
52 return true;
53 }
54 }
55 return false;
56 }
57
58 /**
59 * 将list转化为数组
60 * @param list
61 * @return
62 */
63 public static String[] toArray(List list) {
64 if (null != list && !list.isEmpty()) {
65 String[] arry = new String[list.size()];
66 for (int i = 0; i < list.size(); i++) {
67 arry[i] = list.get(i).toString();
68 }
69 return arry;
70 }
71 return null;
72
73 }
74
75 /**
76 *
77 * 功能说明:将list 转化成字符串 例如 list={1,2,3}转化成1,2,3
78 *
79 * @param list
80 * @return String
81 * @author chh
82 * @May 23, 2012
83 */
84 public static String toString(List<String> list) {
85 if (null == list || list.isEmpty())
86 return "";
87 StringBuffer sb = new StringBuffer();
88 for (int i = 0; i < list.size(); i++) {
89 String str = (String) list.get(i);
90 if (i == list.size() - 1) {
91 sb.append(str);
92 } else {
93 sb.append(str + ",");
94 }
95
96 }
97 return sb.toString();
98 }
99
100 /**
101 * 这种方法适合用来比较List中是否包含某个元素的问题 比较传入List list中是否含有与传入的String str相同的元素
102 *
103 * @param list
104 * @param str
105 * @return true 重复 false 不重复
106 * @throws Exception
107 */
108 public static boolean isItEquals(List list, String str) {
109 for (int i = 0; i < list.size(); i++) {
110 if (str.equals(list.get(i).toString())) {
111 return true;
112 }
113 }
114 return false;
115 }
116
117 }
/** * <p>list操作的工具类</p> */public class ListUtil {/** * 过滤掉list里面才重复项 * * @param list * @return List */public static List<String> filterRepeat(List<String> list){int length = list.size();for(int i = 0;i < length - 1;i++){String temp = list.get(i).toString();for(int j = i + 1;j < length;j++){if(temp.equals(list.get(j))){list.remove(j);j--;length--;}}}return list;}/** * 判断list是否null或者长度为零，常用于从数据库取对象后的判断 * * @param list * @return true:空 false：非空 */public static boolean isNull(List list) {if (null == list || list.size() == 0) {return true;} else {return false;}}/** * list 是否有存在字符串value的值 * * @param list * 链表 * @param value * 值 * @return true: 存在，false：不存在 */public static boolean valueIsExit(List list, String value) {for (int i = 0; i < list.size(); i++) {if (value.equals(list.get(i).toString())) {return true;}}return false;}/** * 将list转化为数组 * @param list * @return */public static String[] toArray(List list) {if (null != list && !list.isEmpty()) {String[] arry = new String[list.size()];for (int i = 0; i < list.size(); i++) {arry[i] = list.get(i).toString();}return arry;}return null;
}/** * * 功能说明:将list 转化成字符串 例如 list={1,2,3}转化成1,2,3 * * @param list * @return String * @author chh * @May 23, 2012 */public static String toString(List<String> list) {if (null == list || list.isEmpty())return "";StringBuffer sb = new StringBuffer();for (int i = 0; i < list.size(); i++) {String str = (String) list.get(i);if (i == list.size() - 1) {sb.append(str);} else {sb.append(str + ",");}
}return sb.toString();}/** * 这种方法适合用来比较List中是否包含某个元素的问题 比较传入List list中是否含有与传入的String str相同的元素 * * @param list * @param str * @return true 重复 false 不重复 * @throws Exception */public static boolean isItEquals(List list, String str) {for (int i = 0; i < list.size(); i++) {if (str.equals(list.get(i).toString())) {return true;}}return false;}}