JAVA String 工具类

java StringUtil 字符串工具类

import java.util.ArrayList;

import java.util.LinkedHashSet;

import java.util.Set;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

 

public class StringUtil {

 

@SuppressWarnings("unchecked")

public static String[] split(String str, String splitsign) {

int index;

if (str == null || splitsign == null) {

return null;

}

ArrayList al = new ArrayList();

while ((index = str.indexOf(splitsign)) != -1) {

al.add(str.substring(0, index));

str = str.substring(index + splitsign.length());

}

al.add(str);

return (String[]) al.toArray(new String[0]);

}

 

public static String replace(String from, String to, String source) {

if (source == null || from == null || to == null)

return null;

StringBuffer str = new StringBuffer("");

int index = -1;

while ((index = source.indexOf(from)) != -1) {

str.append(source.substring(0, index) + to);

source = source.substring(index + from.length());

index = source.indexOf(from);

}

str.append(source);

return str.toString();

}

 

public static String htmlencode(String str) {

if (str == null) {

return null;

}

return replace(""", """, replace("<", "<", str));

}

 

public static String htmldecode(String str) {

if (str == null) {

return null;

}

 

return replace(""", """, replace("<", "<", str));

}

 

private static final String _BR = "
";

 

public static String htmlshow(String str) {

if (str == null) {

return null;

}

 

str = replace("<", "<", str);

str = replace(" ", " ", str);

str = replace("\r\n", _BR, str);

str = replace("\n", _BR, str);

str = replace("\t", "    ", str);

return str;

}

 

public static String toLength(String str, int length) {

if (str == null) {

return null;

}

if (length <= 0) {

return "";

}

try {

if (str.getBytes("GBK").length <= length) {

return str;

}

} catch (Exception e) {

}

StringBuffer buff = new StringBuffer();

 

int index = 0;

char c;

length -= 3;

while (length > 0) {

c = str.charAt(index);

if (c < 128) {

length--;

} else {

length--;

length--;

}

buff.append(c);

index++;

}

buff.append("...");

return buff.toString();

}

 

public static boolean isInteger(String str) {

Pattern pattern = Pattern.compile("^[-\\+]?[\\d]+$");

return pattern.matcher(str).matches();

}

 

public static boolean isDouble(String str) {

Pattern pattern = Pattern.compile("^[-\\+]?\\d+\\.\\d+$");

return pattern.matcher(str).matches();

}

 

public static boolean isLetter(String str) {

if (str == null || str.length() < 0) {

return false;

}

Pattern pattern = Pattern.compile("[\\w\\.-_]*");

return pattern.matcher(str).matches();

}

 

public static String parse(String content) {

String email = null;

if (content == null || content.length() < 1) {

return email;

}

// 找出含有@

int beginPos;

int i;

String token = "@";

String preHalf = "";

String sufHalf = "";

 

beginPos = content.indexOf(token);

if (beginPos > -1) {

// 前项扫描

String s = null;

i = beginPos;

while (i > 0) {

s = content.substring(i - 1, i);

if (isLetter(s))

preHalf = s + preHalf;

else

break;

i--;

}

// 后项扫描

i = beginPos + 1;

while (i < content.length()) {

s = content.substring(i, i + 1);

if (isLetter(s))

sufHalf = sufHalf + s;

else

break;

i++;

}

// 判断合法性

email = preHalf + "@" + sufHalf;

if (isEmail(email)) {

return email;

}

}

return null;

}

 

public static boolean isEmail(String email) {

if (email == null || email.length() < 1 || email.length() > 256) {

return false;

}

Pattern pattern = Pattern

.compile("^\\w+([-+.]\\w+)*@\\w+([-.]\\w+)*\\.\\w+([-.]\\w+)*$");

return pattern.matcher(email).matches();

}

 

public static boolean isChinese(String str) {

Pattern pattern = Pattern.compile("[\u0391-\uFFE5]+$");

return pattern.matcher(str).matches();

}

 

public static boolean isBlank(String str) {

return str == null || str.trim().length() == 0;

}

 

public static boolean isPrime(int x) {

if (x <= 7) {

if (x == 2 || x == 3 || x == 5 || x == 7)

return true;

}

int c = 7;

if (x % 2 == 0)

return false;

if (x % 3 == 0)

return false;

if (x % 5 == 0)

return false;

int end = (int) Math.sqrt(x);

while (c <= end) {

if (x % c == 0) {

return false;

}

c += 4;

if (x % c == 0) {

return false;

}

c += 2;

if (x % c == 0) {

return false;

}

c += 4;

if (x % c == 0) {

return false;

}

c += 2;

if (x % c == 0) {

return false;

}

c += 4;

if (x % c == 0) {

return false;

}

c += 6;

if (x % c == 0) {

return false;

}

c += 2;

if (x % c == 0) {

return false;

}

c += 6;

}

return true;

}

 

public static String hangeToBig(String str) {

double value;

try {

value = Double.parseDouble(str.trim());

} catch (Exception e) {

return null;

}

char[] hunit = { '拾', '佰', '仟' }; // 段内位置表示

char[] vunit = { '万', '亿' }; // 段名表示

char[] digit = { '零', '壹', '贰', '叁', '肆', '伍', '陆', '柒', '捌', '玖' }; // 数字表示

long midVal = (long) (value * 100); // 转化成整形

String valStr = String.valueOf(midVal); // 转化成字符串

 

String head = valStr.substring(0, valStr.length() - 2); // 取整数部分

String rail = valStr.substring(valStr.length() - 2); // 取小数部分

 

String prefix = ""; // 整数部分转化的结果

String suffix = ""; // 小数部分转化的结果

// 处理小数点后面的数

if (rail.equals("00")) { // 如果小数部分为0

suffix = "整";

} else {

suffix = digit[rail.charAt(0) - '0'] + "角"

+ digit[rail.charAt(1) - '0'] + "分"; // 否则把角分转化出来

}

// 处理小数点前面的数

char[] chDig = head.toCharArray(); // 把整数部分转化成字符数组

char zero = '0'; // 标志'0'表示出现过0

byte zeroSerNum = 0; // 连续出现0的次数

for (int i = 0; i < chDig.length; i++) { // 循环处理每个数字

int idx = (chDig.length - i - 1) % 4; // 取段内位置

int vidx = (chDig.length - i - 1) / 4; // 取段位置

if (chDig[i] == '0') { // 如果当前字符是0

zeroSerNum++; // 连续0次数递增

if (zero == '0') { // 标志

zero = digit[0];

} else if (idx == 0 && vidx > 0 && zeroSerNum < 4) {

prefix += vunit[vidx - 1];

zero = '0';

}

continue;

}

zeroSerNum = 0; // 连续0次数清零

if (zero != '0') { // 如果标志不为0,则加上,例如万,亿什么的

prefix += zero;

zero = '0';

}

prefix += digit[chDig[i] - '0']; // 转化该数字表示

if (idx > 0)

prefix += hunit[idx - 1];

if (idx == 0 && vidx > 0) {

prefix += vunit[vidx - 1]; // 段结束位置应该加上段名如万,亿

}

}

 

if (prefix.length() > 0)

prefix += '圆'; // 如果整数部分存在,则有圆的字样

return prefix + suffix; // 返回正确表示

}

 

@SuppressWarnings("unused")

private static String removeSameString(String str) {

Set mLinkedSet = new LinkedHashSet();// set集合的特征：其子集不可以重复

String[] strArray = str.split(" ");// 根据空格(正则表达式)分割字符串

StringBuffer sb = new StringBuffer();

 

for (int i = 0; i < strArray.length; i++) {

if (!mLinkedSet.contains(strArray[i])) {

mLinkedSet.add(strArray[i]);

sb.append(strArray[i] + " ");

}

}

System.out.println(mLinkedSet);

return sb.toString();

}

 

public static String encoding(String src) {

if (src == null)

return "";

StringBuilder result = new StringBuilder();

if (src != null) {

src = src.trim();

for (int pos = 0; pos < src.length(); pos++) {

switch (src.charAt(pos)) {

case '"':

result.append(""");

break;

case '<':

result.append("<");

break;

case '>':

result.append(">");

break;

case '\'':

result.append("'");

break;

case '&':

result.append("&");

break;

case '%':

result.append("&pc;");

break;

case '_':

result.append("&ul;");

break;

case '#':

result.append("&shap;");

break;

case '?':

result.append("&ques;");

break;

default:

result.append(src.charAt(pos));

break;

}

}

}

return result.toString();

}

 

public static boolean isHandset(String handset) {

try {

String regex = "^1[\\d]{10}$";

Pattern pattern = Pattern.compile(regex);

Matcher matcher = pattern.matcher(handset);

return matcher.matches();

 

} catch (RuntimeException e) {

return false;

}

}

 

public static String decoding(String src) {

if (src == null)

return "";

String result = src;

result = result.replace(""", """).replace("'", "\'");

result = result.replace("<", "<").replace(">", ">");

result = result.replace("&", "&");

result = result.replace("&pc;", "%").replace("&ul", "_");

result = result.replace("&shap;", "#").replace("&ques", "?");

return result;

}

 

public static void main(String[] args) {

String source = "abcdefgabcdefgabcdefgabcdefgabcdefgabcdefg";

String from = "efg";

String to = "房贺威";

System.out.println("在字符串source中，用to替换from，替换结果为："

+ replace(from, to, source));

System.out.println("返回指定字节长度的字符串："

+ toLength("abcdefgabcdefgabcdefgabcdefgabcdefgabcdefg", 9));

System.out.println("判断是否为整数：" + isInteger("+0"));

System.out.println("判断是否为浮点数，包括double和float：" + isDouble("+0.36"));

System.out.println("判断输入的字符串是否符合Email样式：" +

isEmail("fhwbj@163.com"));

System.out.println("判断输入的字符串是否为纯汉字：" + isChinese("你好！"));

System.out.println("判断输入的数据是否是质数：" + isPrime(12));

System.out.println("人民币转换成大写：" + hangeToBig("10019658"));

System.out.println("去掉字符串中重复的子字符串：" + removeSameString("100 100 9658"));

System.out.println("过滤特殊字符：" + encoding("100"s<>fdsd100 9658"));

System.out.println("判断是不是合法的手机号码：" + isHandset("15981807340"));

 

System.out.println("从字符串中取值Email：" + parse("159818 fwhbj@163.com07340"));

}

}