下划线分割的表名、字段名转驼峰的工具类

//无需引第三方包

import org.apache.commons.lang.StringUtils;

public class ConvertUtil {


public static String firstUpperCamelCase(String str) {
if (StringUtils.isNotBlank(str)) {
str = str.replace("T_", "");
str = str.toLowerCase();
String[] strs = str.split("_");
if (strs.length == 1) {
return firstLetterUpper(str);
} else {
String convertedStr = "";
for (int i = 0; i < strs.length; i++) {
convertedStr += firstLetterUpper(strs[i]);
}
return convertedStr;
}
}
return str;
}


public static String firstLowerCamelCase(String str) {
if (StringUtils.isNotBlank(str)) {
str = str.replace("T_", "");
str = str.toLowerCase();
String[] strs = str.split("_");
if (strs.length == 1) {
return allLower(str);
} else {
String convertedStr = "";
for (int i = 1; i < strs.length; i++) {
convertedStr += firstLetterUpper(strs[i]);
}
return strs[0] + convertedStr;
}
}
return str;
}


public static String firstLetterUpper(String str) {
if (StringUtils.isNotBlank(str)) {
str = str.replace("T_", "");
str = str.toLowerCase();
return str.substring(0, 1).toUpperCase()
+ str.substring(1, str.length());
}
return str;
}


public static String allUpper(String str) {
if (StringUtils.isNotBlank(str)) {
str = str.replace("T_", "");
str = str.toLowerCase();
String[] strs = str.split("_");
if (strs.length == 1) {
return str.toUpperCase();
} else {
String convertedStr = "";
for (int i = 0; i < strs.length; i++) {
convertedStr += strs[i].toUpperCase();
}
return convertedStr;
}
}
return str;
}


public static String allLower(String str) {
if (StringUtils.isNotBlank(str)) {
str = str.replace("T_", "");
str = str.toLowerCase();
String[] strs = str.split("_");
if (strs.length == 1) {
return str.toLowerCase();
} else {
String convertedStr = "";
for (int i = 0; i < strs.length; i++) {
convertedStr += strs[i].toLowerCase();
}
return convertedStr;
}
}
return str;
}


public static void main(String[] args) {
String s = "e_wfAA_T_AAD_dAAAA_AAdd";
System.out.println(firstUpperCamelCase(s));
System.out.println(firstLowerCamelCase(s));
System.out.println(s.toLowerCase());
}
}