582
java 開發中常用方法
從List中拿出top指的條數數據：
/**
* 取top x條產品類數據
*
* @param sourList 產品類集合
* @param rowsCount 條數
* @return List<ProductInfo>
*/
public static List<ProductInfo> limitProductInfoList(List<ProductInfo> sourList,
int rowsCount) {
List<ProductInfo> tempList = new ArrayList<>();
if (sourList != null) {
int sourListSize = sourList.size();
if (rowsCount < sourListSize) {
int subCount =
sourListSize % rowsCount == 0 ? sourListSize / rowsCount : sourListSize / rowsCount + 1;
int startIndext = 0;
int stopIndext = 0;
for (int i = 0; i < subCount; i++) {
stopIndext =
(i == subCount - 1) ? stopIndext + sourListSize % rowsCount : stopIndext + rowsCount;
tempList = new ArrayList<ProductInfo>(sourList.subList(startIndext, stopIndext));
startIndext = stopIndext;
if (tempList.size() > 0) {
break;
}
}
} else {
tempList = sourList;
}
}
return tempList;
}
比較字符串是否在數組中：
private static String[] StarArray = new String[]{"DHTL", "IHTL", "GPKG", "GDIY", "GCRU"};
ArrayUtils.contains(StarArray, "DHTL")
//驗證對象為null
if (ObjectUtils.equals(sysRole, null)) {
sysRole = this.getRole(systemCode, loginName);
}
//驗證List
if (CollectionUtils.isNotEmpty(sysRoleList)) {
sysRole = sysRoleList.get(0);
}
//驗證字符串-驗證時候忽略空白
if (StringUtils.isBlank(formData.getPost()))｛
｝
//驗證字符串非空
if (StringUtils.isNotEmpty(userCard.getUID()))
/**
* 清除空白字符
*
* @param str
* @return
*/
public static String trimAllWhitespace(String str) {
if (str != null) {
int len = str.length();
if (len > 0) {
char[] dest = new char[len];
int destPos = 0;
for (int i = 0; i < len; ++i) {
char c = str.charAt(i);
if (!Character.isWhitespace(c)) {
dest[destPos++] = c;
}
}
return new String(dest, 0, destPos);
}
}
return str;
}
/**
*list轉換string
* @param list List<String>
* @param separator 分隔符 逗號等
* @return
*/
public static String listToString(List<String> list, char separator) {
return org.apache.commons.lang.StringUtils.join(list.toArray(), separator);
}
/**
*string轉換list
* @param str 分隔符字符串
* @param separator 逗號等
* @return List<String>
*/
public static List<String> stringToList(String str, String separator) {
return java.util.Arrays.asList(str.split(separator));
}
最後更新：2017-11-14 16:04:06