cn.buli_home.utils.common.StringUtils Maven / Gradle / Ivy
package cn.buli_home.utils.common;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Objects;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class StringUtils {
/**
* 判断是否为空
*/
public static boolean isEmpty(String str) {
return Objects.isNull(str) || str.length() == 0;
}
/**
* 判断是否为空(去空格)
*/
public static boolean isEmptyWithoutBlank(String str) {
return isEmpty(replaceBlank(str));
}
/**
* 去空白符
*/
public static String replaceBlank(String str) {
if(isEmpty(str)){
return "";
}
Pattern p = Pattern.compile("\\s*|\t|\r|\n| ");
Matcher m = p.matcher(str);
return m.replaceAll("");
}
/**
* 将 Object 转换为 String
* null或 (不区分大小写), 认定为空
*/
public static String convert2String(Object obj) {
if (obj == null) {
return "";
}
if (obj instanceof String) {
if (((String) obj).equalsIgnoreCase("NULL") || ((String) obj).equalsIgnoreCase("")) {
return "";
}
return (String) obj;
} else {
return obj.toString();
}
}
/**
* 大写第一个字母
*/
public static String upperFirst(String str) {
if (org.apache.commons.lang3.StringUtils.isEmpty(str)) {
return org.apache.commons.lang3.StringUtils.EMPTY;
}
char[] chars = str.toCharArray();
for (int i = 0; i < chars.length; i++) {
char c = chars[i];
if (!Character.isLetter(c)) {
continue;
}
chars[i] = p_upperChar(c);
break;
}
return String.valueOf(chars);
}
/**
* 小写第一个字母
*/
public static String lowerFirst(String str) {
if (org.apache.commons.lang3.StringUtils.isEmpty(str)) {
return org.apache.commons.lang3.StringUtils.EMPTY;
}
char[] chars = str.toCharArray();
for (int i = 0; i < chars.length; i++) {
char c = chars[i];
if (!Character.isLetter(c)) {
continue;
}
chars[i] = p_lowerChar(c);
break;
}
return String.valueOf(chars);
}
/**
* 驼峰转下划线
*/
public static String camel2Underline(String str) {
if (org.apache.commons.lang3.StringUtils.isEmpty(str)) {
return org.apache.commons.lang3.StringUtils.EMPTY;
}
StringBuilder buf = new StringBuilder();
for (int i = 0; i < str.length(); ++i) {
char ch = str.charAt(i);
if (ch >= 'A' && ch <= 'Z') {
char ch_ucase = p_lowerChar(ch);
if (i > 0) {
buf.append('_');
}
buf.append(ch_ucase);
} else {
buf.append(ch);
}
}
return buf.toString();
}
/**
* 下划线转驼峰
*/
public static String underline2Camel(String str) {
if (org.apache.commons.lang3.StringUtils.isEmpty(str)) {
return org.apache.commons.lang3.StringUtils.EMPTY;
}
String[] split = str.split("_");
StringBuilder sb = new StringBuilder(str.length());
for (String s : split) {
sb.append(lowerFirst(s));
}
return sb.toString();
}
/**
* 去掉字符串指定的前缀
* @param str 字符串名称
* @param prefix 前缀数组
*/
public static String removePrefix(String str, String[] prefix) {
if (Objects.isNull(str) || str.length() == 0) {
return "";
} else {
if (null != prefix) {
String[] prefixArray = prefix;
for(int i = 0; i < prefix.length; ++i) {
String pf = prefixArray[i];
if (str.toLowerCase().matches("^" + pf.toLowerCase() + ".*")) {
//截取前缀后面的字符串
return str.substring(pf.length());
}
}
}
return str;
}
}
/**
* 解析成 Integer
*/
public static Integer parseInt(String str) {
String tmpStr = convert2String(str);
if (tmpStr.equals("")) {
return 0;
} else {
int n = 0;
try {
n = (int) Double.parseDouble(tmpStr);
} catch (Exception e) {
return 0;
}
return n;
}
}
/**
* 解析成 Long
*/
public static Long parseLong(String str) {
String tmpStr = convert2String(str);
if (tmpStr.equals("")) {
return 0L;
} else {
long n = 0;
try {
n = Long.parseLong(tmpStr);
} catch (Exception e) {
return 0L;
}
return n;
}
}
/**
* 解析成 Double
*/
public static Double parseDouble(String str) {
String tmpStr = convert2String(str);
if (tmpStr.equals("")) {
return 0.0;
} else {
Double n = 0.0;
try {
n = Double.parseDouble(tmpStr);
} catch (Exception e) {
return 0.0;
}
return n;
}
}
/**
* 解析成 Boolean
*/
public static Boolean parseBoolean(String str) {
if (isEmpty(str)) {
return false;
}
return str.equalsIgnoreCase("true") || str.equalsIgnoreCase("yes");
}
/**
* 分隔字符串, 之后取第n位子字符串
* 🌰: getSplitAtIdx("a,b,c", ",", 1) -> "b"
*/
public static String getSplitAtIdx(String str, String regex, int idx) {
String string = convert2String(str);
String[] array = string.split(regex);
if (array.length > idx) {
return array[idx];
}
return "";
}
/**
* 是否有特殊字符
*/
public static boolean hasSpecialChar(String str) {
String regEx = "[ _`~!@#$%^&*()+=|{}':;',\\[\\].<>/?~！@#￥%……&*（）——+|{}【】‘；：”“’。，、？]|\n|\r|\t";
Pattern p = Pattern.compile(regEx);
Matcher m = p.matcher(str);
return m.find();
}
/**
* 字节长度
*/
public static int bytesLength(String str) {
return convert2String(str).getBytes().length;
}
/**
* base64
*/
public static String base64(String str) {
return Base64.encodeBase64String(convert2String(str).getBytes(StandardCharsets.UTF_8));
}
/**
* md5
*/
public static String md5(String str) {
try {
MessageDigest md5 = MessageDigest.getInstance("MD5");
return Hex.encodeHexString(md5.digest(convert2String(str).getBytes(StandardCharsets.UTF_8)));
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
return "";
}
private static char p_upperChar(char c) {
if (c >= 97) {
c -= 32;
}
return c;
}
private static char p_lowerChar(char c) {
if (c < 97) {
c += 32;
}
return c;
}
}