String有用的工具类
package com.common.string;import java.util.ArrayList;import java.util.LinkedHashSet;import java.util.Set;import java.util.regex.Matcher;import java.util.regex.Pattern;/** * 功能描述：关于字符串的一些实用操作 * * @author Administrator * @Date Jul 18, 2008 * @Time 2:19:47 PM * @version 1.0 */public class StringUtil {/** * 功能描述：分割字符串 * * @param str * String 原始字符串 * @param splitsign * String 分隔符 * @return String[] 分割后的字符串数组 */@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]);}/** * 功能描述：替换字符串 * * @param from * String 原始字符串 * @param to * String 目标字符串 * @param source * String 母字符串 * @return String 替换后的字符串 */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();}/** * 替换字符串，能能够在HTML页面上直接显示(替换双引号和小于号) * * @param str * String 原始字符串 * @return String 替换后的字符串 */public static String htmlencode(String str) {if (str == null) {return null;}return replace("\"", """, replace("<", "<", str));}/** * 替换字符串，将被编码的转换成原始码（替换成双引号和小于号） * * @param str * String * @return String */public static String htmldecode(String str) {if (str == null) {return null;}return replace(""", "\"", replace("<", "<", str));}private static final String _BR = "<br/>";/** * 功能描述：在页面上直接显示文本内容，替换小于号，空格，回车，TAB * * @param str * String 原始字符串 * @return String 替换后的字符串 */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;}/** * 功能描述：返回指定字节长度的字符串 * * @param str * String 字符串 * @param length * int 指定长度 * @return String 返回的字符串 */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();}/** * 功能描述：判断是否为整数 * * @param str * 传入的字符串 * @return 是整数返回true,否则返回false */public static boolean isInteger(String str) {Pattern pattern = Pattern.compile("^[-\\+]?[\\d]+$");return pattern.matcher(str).matches();}/** * 判断是否为浮点数，包括double和float * * @param str * 传入的字符串 * @return 是浮点数返回true,否则返回false */public static boolean isDouble(String str) {Pattern pattern = Pattern.compile("^[-\\+]?\\d+\\.\\d+$");return pattern.matcher(str).matches();}/** * 判断是不是合法字符 c 要判断的字符 */public static boolean isLetter(String str) {if (str == null || str.length() < 0) {return false;}Pattern pattern = Pattern.compile("[\\w\\.-_]*");return pattern.matcher(str).matches();}/** * 从指定的字符串中提取Email content 指定的字符串 * * @param content * @return */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;elsebreak;i--;}// 后项扫描i = beginPos + 1;while (i < content.length()) {s = content.substring(i, i + 1);if (isLetter(s))sufHalf = sufHalf + s;elsebreak;i++;}// 判断合法性email = preHalf + "@" + sufHalf;if (isEmail(email)) {return email;}}return null;}/** * 功能描述：判断输入的字符串是否符合Email样式. * * @param str * 传入的字符串 * @return 是Email样式返回true,否则返回false */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+)*$");return pattern.matcher(email).matches();}/** * 功能描述：判断输入的字符串是否为纯汉字 * * @param str * 传入的字符窜 * @return 如果是纯汉字返回true,否则返回false */public static boolean isChinese(String str) {Pattern pattern = Pattern.compile("[\u0391-\uFFE5]+$");return pattern.matcher(str).matches();}/** * 功能描述：是否为空白,包括null和"" * * @param str * @return */public static boolean isBlank(String str) {return str == null || str.trim().length() == 0;}/** * 功能描述：判断是否为质数 * * @param x * @return */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;}/** * 功能描述：人民币转成大写 * * @param str * 数字字符串 * @return String 人民币转换成大写后的字符串 */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0suffix = "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0byte 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0zeroSerNum++; // 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}/** * 功能描述：去掉字符串中重复的子字符串 * * @param str * 原字符串，如果有子字符串则用空格隔开以表示子字符串 * @return String 返回去掉重复子字符串后的字符串 */@SuppressWarnings("unused")private static String removeSameString(String str) {Set<String> mLinkedSet = new LinkedHashSet<String>();// 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();}/** * 功能描述：过滤特殊字符 * * @param src * @return */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();}/** * 功能描述：判断是不是合法的手机号码 * * @param handset * @return boolean */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;}}/** * 功能描述：反过滤特殊字符 * * @param src * @return */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;}/** * @param args */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.com// 07340"));}}
