Java String工具类StringHelper，工具类stringhelper,主要功能是字符串与Inp

Java String工具类StringHelper，工具类stringhelper,主要功能是字符串与Inp

主要功能是字符串与InputStream、byte数组的转换，判断手机号，判断中文、判断邮箱、判断邮编、四舍五入、取几位小数等。 代码如下： ```javaimport java.io.BufferedReader;import java.io.ByteArrayInputStream;import java.io.ByteArrayOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.io.StringWriter;import java.math.BigDecimal;import java.util.regex.Matcher;import java.util.regex.Pattern;

import android.text.TextUtils;

public class StringHelper {

private static StringHelper util;public final String[] PHONE_PREFIX = new String[] { "130", "131", "132",        "133", "134", "135", "136", "137", "138", "139", "150", "151",        "152", "153", "154", "155", "156", "157", "158", "159", "180",        "181", "182", "183", "184", "185", "186", "187", "188", "189" };public static StringHelper getInstance() {    if (util == null) {        util = new StringHelper();    }    return util;}private StringHelper() {    super();}/** * InputStream转byte数组 *  * @param is * @return */public byte[] stream2Byte(InputStream is) {    byte[] in_b = null;    try {        ByteArrayOutputStream os = new ByteArrayOutputStream();        int i = -1;        while ((i = is.read()) != -1) {            os.write(i);        }        in_b = os.toByteArray();    } catch (IOException e) {        // TODO Auto-generated catch block        e.printStackTrace();    }    return in_b;}/** * InputStream 转String *  * @param is * @return */public String stream2String(InputStream is) {    try {        BufferedReader br = new BufferedReader(new InputStreamReader(is));        StringWriter sw = new StringWriter();        int i = -1;        while ((i = br.read()) != -1) {            sw.write(i);        }        return sw.getBuffer().toString();    } catch (Exception e) {        // TODO: handle exception    }    return null;}/** * 字符串转InputStream *  * @param str * @return */public InputStream string2Stream(String str) {    ByteArrayInputStream is = new ByteArrayInputStream(str.getBytes());    return is;}/** * byte数组转InputStream *  * @param by * @return */public InputStream byte2Stream(byte[] by) {    ByteArrayInputStream stream = new ByteArrayInputStream(by);    return stream;}/** * 判断是否是中文字符,只能判断部分CJK字符 *  * @param str * @return */public boolean isChina(String str) {    Pattern p = Pattern.compile("[\\u4E00-\\u9FBF]+");    Matcher m = p.matcher(str);    return m.matches();}/** * 根据Unicode编码完美的判断中文汉字和符号 *  * @param c * @return */private boolean isChinese(char c) {    Character.UnicodeBlock ub = Character.UnicodeBlock.of(c);    if (ub == Character.UnicodeBlock.CJK_UNIFIED_IDEOGRAPHS            || ub == Character.UnicodeBlock.CJK_COMPATIBILITY_IDEOGRAPHS            || ub == Character.UnicodeBlock.CJK_UNIFIED_IDEOGRAPHS_EXTENSION_A            || ub == Character.UnicodeBlock.CJK_UNIFIED_IDEOGRAPHS_EXTENSION_B            || ub == Character.UnicodeBlock.CJK_SYMBOLS_AND_PUNCTUATION            || ub == Character.UnicodeBlock.HALFWIDTH_AND_FULLWIDTH_FORMS            || ub == Character.UnicodeBlock.GENERAL_PUNCTUATION) {        return true;    }    return false;}/** * 判断是否包含中文汉字 *  * @param strName * @return */public boolean isChineseHave(String strName) {    char[] ch = strName.toCharArray();    for (int i = 0; i < ch.length; i++) {        char c = ch[i];        if (isChinese(c)) {            return true;        }    }    return false;}/** * 判断是否只有中文汉字 *  * @param strName * @return */public boolean isChineseAll(String strName) {    char[] ch = strName.toCharArray();    for (int i = 0; i < ch.length; i++) {        char c = ch[i];        if (!isChinese(c)) {            return false;        }    }    return true;}/** * 判断邮政编码 *  * @param str * @return */public boolean isCard(String str) {    Pattern p = Pattern.compile("[1-9]\\d{5}(?!\\d)");    Matcher m = p.matcher(str);    return m.matches();}/** * 检测邮箱合法性 *  * @param email * @return */public boolean isEmail(String email) {    if ((email == null) || (email.trim().length() == 0)) {        return false;    }    String regEx = "^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\\.[a-zA-Z]{2,4}$";    Pattern p = Pattern.compile(regEx);    Matcher m = p.matcher(email.trim().toLowerCase());    return m.find();}/** * 检查手机号码合法性 *  * @param mdn * @return */public boolean isPhoneNumber(String mdn, boolean checkLen) {    if (mdn == null || mdn.equals("")) {        return false;    }    if (mdn.startsWith("+86")) {        mdn = mdn.substring(3);    }    if (checkLen &amp;&amp; mdn.length() != 11) {        return false;    }    boolean flag = false;    String p = mdn.length() > 3 ? mdn.substring(0, 3) : mdn;    for (int i = 0; i < PHONE_PREFIX.length; i++) {        if (p.equals(PHONE_PREFIX[i])) {            flag = true;            break;        }    }    if (!flag) {        return false;    }    return true;}/** * 判断字符串中是否是整型数字 *  * @param str * @return */public boolean isInt(String str) {    if (!TextUtils.isEmpty(str)) {        return str.toString().matches("^[-]?\\d+$");    }    return false;}/** * 字符串转整型 *  * @param str * @return */public int getInt(String str) {    if (!TextUtils.isEmpty(str)) {        String newValue = str.toString().replaceAll("\\D+", "");        if (!TextUtils.isEmpty(newValue)) {            return 0;        }        return Integer.parseInt(newValue);    }    return 0;}/** * 判断字符串中是否是Double *  * @param str * @return */public boolean isDouble(String str) {    if (!TextUtils.isEmpty(str)) {        return str.toString().matches("^\\d+(\\.[\\d]+)?$");    }    return false;}/** * 字符串转Double *  * @param str * @return */public double getDouble(String str) {    if (!TextUtils.isEmpty(str)) {        if (isDouble(str))            return Double.parseDouble(str);        else            return 0.0D;    }    return 0.0D;}/** * 字符串转Double,并进行四舍五入 *  * @param v * @param scale * @return */public double getDouble(String str, int scale) {    Double v = getDouble(str);    return getDouble(v, scale);}/** * Double进行四舍五入 *  * @param v * @param scale * @return */public double getDouble(Double v, int scale) {    if (scale < 0) {        scale = 0;    }    BigDecimal b = new BigDecimal(v);    BigDecimal one = new BigDecimal("1");    return b.divide(one, scale, BigDecimal.ROUND_HALF_UP).doubleValue();}/** * 得到指定位数的小数 * @param v * @param scale * @return */public String getDecimals(Double v, int scale) {    return String.format("%." + String.valueOf(scale) + "f", v);}/** * 得到指定位数的小数 * @param v * @param scale * @return */public String getDecimals(String v, int scale) {    return getDecimals(getDouble(v), scale);}

}```