com.base4j.mybatis.sql.util.SqlStringUtil Maven / Gradle / Ivy
package com.base4j.mybatis.sql.util;
import com.base4j.mybatis.sql.entity.Style;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* Created by USER on 2017-03-21.
*/
public class SqlStringUtil {
private static Pattern STR_PATTERN = Pattern.compile("_[a-z]");
/**
* 空
*
* @param str
* @return
*/
public static boolean isEmpty(String str) {
return str == null || str.length() == 0;
}
/**
* 非空
*
* @param str
* @return
*/
public static boolean isNotEmpty(String str) {
return !isEmpty(str);
}
/**
* 将驼峰风格替换为下划线风格
*/
public static String camelhumpToUnderline(String str) {
final int size;
final char[] chars;
final StringBuilder sb = new StringBuilder(
(size = (chars = str.toCharArray()).length) * 3 / 2 + 1);
char c;
for (int i = 0; i < size; i++) {
c = chars[i];
if (isUppercaseAlpha(c)) {
sb.append('_').append(toLowerAscii(c));
} else {
sb.append(c);
}
}
return sb.charAt(0) == '_' ? sb.substring(1) : sb.toString();
}
/**
* 根据指定的样式进行转换
*
* @param str
* @param style
* @return
*/
public static String convertByStyle(String str, Style style) {
switch (style) {
case camelhump:
return camelhumpToUnderline(str);
case uppercase:
return str.toUpperCase();
case lowercase:
return str.toLowerCase();
case camelhumpAndLowercase:
return camelhumpToUnderline(str).toLowerCase();
case camelhumpAndUppercase:
return camelhumpToUnderline(str).toUpperCase();
case normal:
default:
return str;
}
}
/**
* 将下划线风格替换为驼峰风格
*/
public static String underlineToCamelhump(String str) {
Matcher matcher =STR_PATTERN.matcher(str);
StringBuilder builder = new StringBuilder(str);
for (int i = 0; matcher.find(); i++) {
builder.replace(matcher.start() - i, matcher.end() - i, matcher.group().substring(1).toUpperCase());
}
if (Character.isUpperCase(builder.charAt(0))) {
builder.replace(0, 1, String.valueOf(Character.toLowerCase(builder.charAt(0))));
}
return builder.toString();
}
public static boolean isUppercaseAlpha(char c) {
return (c >= 'A') && (c <= 'Z');
}
public static boolean isLowercaseAlpha(char c) {
return (c >= 'a') && (c <= 'z');
}
public static char toUpperAscii(char c) {
if (isLowercaseAlpha(c)) {
c -= (char) 0x20;
}
return c;
}
public static char toLowerAscii(char c) {
if (isUppercaseAlpha(c)) {
c += (char) 0x20;
}
return c;
}
}