String类的一些常用操作方法

package com.liveyc.framework.util;

import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.text.DecimalFormat;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.StringTokenizer;

import org.apache.commons.collections.CollectionUtils;


/** 
* @author aitf 
* @version 创建时间：2016年12月15日 下午2:38:30 
* 类说明 
*/
public class StringUtil {

    /**
     * <li>判断字符串是否为空值</li>
     * <li>NULL、空格均认为空值</li>.
     * 
     * @param value
     *            the value
     * 
     * @return true, if checks if is empty
     */
    public static boolean isEmpty(String value) {
        return null == value || "".equals(value.trim());
    }
    

    /**
     * 去除,分隔符，用于金额数值去格式化.
     * 
     * @param value
     *            the value
     * 
     * @return the string
     */
    public static String decimal(String value) {
        if (null == value || "".equals(value.trim())) {
            return "0";
        } else {
            return value.replaceAll(",", "");
        }
    }

    /**
     * 在数组中查找字符串.
     * 
     * @param params
     *            the params
     * @param name
     *            the name
     * @param ignoreCase
     *            the ignore case
     * 
     * @return the int
     */
    public static int indexOf(String[] params, String name, boolean ignoreCase) {
        if (params == null)
            return -1;
        for (int i = 0, j = params.length; i < j; i++) {
            if (ignoreCase && params[i].equalsIgnoreCase(name)) {
                return i;
            } else if (params[i].equals(name)) {
                return i;
            }
        }
        return -1;
    }

    /**
     * 查询Str2在Str1中出现几次
     * 
     * @param str1
     * @param str2
     * @return
     */
    public static int indexAllOf(String str1, String str2) {
        int he = 0;
        for (int i = 0; i < str1.length(); i++) {
            int t = str1.indexOf(str2, i);
            if (i == t) {
                he++;
            }
        }
        return he;
    }

    /**
     * 将字符转数组.
     * 
     * @param str
     *            the str
     * 
     * @return the string[]
     */
    public static String[] toArr(String str) {
        String inStr = str;
        String a[] = null;
        try {
            if (null != inStr) {
                StringTokenizer st = new StringTokenizer(inStr, ",");
                if (st.countTokens() > 0) {
                    a = new String[st.countTokens()];
                    int i = 0;
                    while (st.hasMoreTokens()) {
                        a[i++] = st.nextToken();
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return a;
    }

    /**
     * 将字符转数组.
     * 
     * @param str
     *            the str
     * @param splitChar
     *            the split char
     * 
     * @return the string[]
     */
    public static String[] toArr(String str, String splitChar) {
        String inStr = str;
        String a[] = null;
        try {
            if (null != inStr) {
                StringTokenizer st = new StringTokenizer(inStr, splitChar);
                if (st.countTokens() > 0) {
                    a = new String[st.countTokens()];
                    int i = 0;
                    while (st.hasMoreTokens()) {
                        a[i++] = st.nextToken();
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return a;
    }

    /**
     * 字符串数组包装成字符串.
     * 
     * @param ary
     *            the ary
     * @param s
     *            包装符号如 ' 或 "
     * 
     * @return the string
     */
    public static String toStr(String[] ary, String s) {
        if (ary == null || ary.length < 1)
            return "";
        StringBuffer bf = new StringBuffer();
        bf.append(s);
        bf.append(ary[0]);
        for (int i = 1; i < ary.length; i++) {
            bf.append(s).append(",").append(s);
            bf.append(ary[i]);
        }
        bf.append(s);
        return bf.toString();
    }

    /**
     * 得到字符的编码格式
     * 
     * @param str
     * @return
     */
    public static String getEncoding(String str) {
        String encode = "GB2312";
        try {
            if (str.equals(new String(str.getBytes(encode), encode))) {
                String s = encode;
                return s;
            }
        } catch (Exception exception) {
        }
        encode = "ISO-8859-1";
        try {
            if (str.equals(new String(str.getBytes(encode), encode))) {
                String s1 = encode;
                return s1;
            }
        } catch (Exception exception1) {
        }
        encode = "UTF-8";
        try {
            if (str.equals(new String(str.getBytes(encode), encode))) {
                String s2 = encode;
                return s2;
            }
        } catch (Exception exception2) {
        }
        encode = "GBK";
        try {
            if (str.equals(new String(str.getBytes(encode), encode))) {
                String s3 = encode;
                return s3;
            }
        } catch (Exception exception3) {
        }
        return "";
    }


    /**
     * utf8转码 Description :.
     * 
     * @param str
     *            the str
     * 
     * @return the string
     */
    public static String utf8Decoder(String str) {
        try {
            if (str != null) {
                return URLDecoder.decode(str, "UTF-8");
            }
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return str;
    }

    
    public static String changeCharset(String str, String oldCharset, String newCharset)  
            throws UnsupportedEncodingException {  
        if (str != null) {  
            // 用旧的字符编码解码字符串。解码可能会出现异常。  
            byte[] bs = str.getBytes(oldCharset);  
            // 用新的字符编码生成字符串  
            return new String(bs, newCharset);  
        }  
        return null;  
    }  

    
    /**
     * 过滤掉高亮的html
     * @param str
     * @return
     */
    public static String htmlFilter(String str) {
        if (isEmpty(str)) {
            return str;
        }
        str = str.replace("<font color='red'>", "");
        str = str.replace("<font color='blue'>", "");
        str = str.replace("</font>", "");
        
        return str;
    }
    
    public static String trimString(String str){
        if(isEmpty(str)){
            return str;
        }
        return str.trim();
    }
    
    
    public static String encodeToUtf(String str) throws Exception {
        if(isEmpty(str)){
            return str;
        }
        return new String(str.getBytes("iso-8859-1"), "UTF-8");
    }
    
    /**
     * 根据身份证号转性别
     * @param sfzh
     * @return
     */
    public static String converToSex(String sfzh){
        int sex = 0;
        if(StringUtil.isEmpty(sfzh)){
            return "";
        }else{
            if(sfzh.length()==15){
                sex = Integer.parseInt(sfzh.substring(13,14));
            }else if(sfzh.length()==18){
                sex = Integer.parseInt(sfzh.substring(16,17));
            }
            if(sex%2 == 0){
                return "女";
            }else{
                return "男";
            }
        }
    }
    
    /**
     * 设置地址的Map,并去重
     * @param addrMap
     * @param fromType
     * @param addrs
     */
    public static void setAddr2Map(Map addrMap,String addrs,String fromType){
        String[] addrls = null ;
        if(addrMap==null){
            addrMap = new HashMap();
        }
        if(addrMap.containsKey(fromType)){
            String strAddr = (String)addrMap.get(fromType);
            if(strAddr!=null && strAddr.trim().length()>0){
                addrls = strAddr.split(",");
            }
            
            if(!isExsit(addrls,addrs)){
                strAddr +=","+addrs;
                addrMap.put(fromType, strAddr);
            }
        }else{
            addrMap.put(fromType, addrs);
        }
    }
    
    
    /**
     * 字符口串是否在数据组存在
     * @param addrls
     * @param addrs
     * @return
     */
    private static boolean isExsit(String[] addrls,String addrs){
        if(addrls!=null && addrls.length>0){
            for(int i=0;i<addrls.length;i++){
                if(addrls[i].equals(addrs)){
                    return true;
                }
            }
        }
        return false;
    }
    /**
     * 把Map转换成String
     * @param addrMap
     * @return
     */
    public static String convMap2String(Map addrMap){
        StringBuilder tempBuf =new StringBuilder();
        Iterator<Map.Entry> it = addrMap.entrySet().iterator();  
        while (it.hasNext()) {
            Map.Entry<String, String> entry = it.next();
            String fldName = entry.getKey();
            String fldValue = entry.getValue();
            tempBuf.append(fldValue).append("(").append(fldName).append(");");
        }
        return tempBuf.toString();
    }

    //字节转换
    public static String formetFileSize(long fileS) {

        DecimalFormat df = new DecimalFormat("#.00");
        String fileSizeString = "";
        if (fileS < 1024) {
            fileSizeString = df.format((long) fileS) + "B";
        } else if (fileS < 1048576) {
            fileSizeString = df.format((long) fileS / 1024) + "KB";
        } else if (fileS < 1073741824) {
            fileSizeString = df.format((long) fileS / 1048576) + "MB";
        } else if(fileS < 1099511627776l) {
            fileSizeString = df.format((long) fileS / 1073741824) + "GB";
        } else{
            fileSizeString = df.format((long) fileS / 1099511627776l) + "TB";
        }
            return fileSizeString;
        }
    
    public static void main(String[] args) {
        
        long a = 1948065583104l;
        System.out.println(formetFileSize(a));
    }

}