JAVA常用函数1

/**
* 将某个日期以固定格式转化成字符串
*
* @param date
* @return String
*/
public static String dateToStr(java.util.Date date)
{
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String str = sdf.format(date);
return str;
}

/**
* 判断任意一个整数是否素数
*
* @param n
* @return boolean
*/
public static boolean isPrimes(int n)
{
for (int i = 2; i <= Math.sqrt(n); i++)
{
if (n % i == 0)
{
return false;
}
}
return true;
}

/**
* 获得任意一个整数的阶乘，递归
*
* @param n
* @return n!
*/
public static int factorial(int n)
{
if (n == 1)
{
return 1;
}
return n * factorial(n - 1);
}

/**
* 将指定byte数组以16进制的形式打印到控制台
*
* @param hint
* String
* @param b
* byte[]
* @return void
*/
public static void printHexString(String hint, byte[] b)
{
System.out.print(hint);
for (int i = 0; i < b.length; i++)
{
String hex = Integer.toHexString(b[i] & 0xFF);
if (hex.length() == 1)
{
hex = '0' + hex;
}
System.out.print(hex.toUpperCase() + " ");
}
System.out.println("");
}

wait(); //线程等待
notify(); //激活一个线程

/* * Db.java
Created on 2007年8月20日, 上午 8:37
*/
import java.io.*;
import java.sql.*;
import java.util.Properties;
public class Db {
private String driver;
private String url;
private String user;
private String password;
private Connection conn;
private Statement stm;
private ResultSet rs;
public Db(){
this("DBConf.properties");
}
public Db(String conf) {
loadProperties(conf);
setConn();
}
public Connection getConn(){
return this.conn;
}
//handle the properties file to get the informations for connection
private void loadProperties(String conf){
Properties props = new Properties();
try {
props.load(new FileInputStream(conf));
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
this.driver = props.getProperty("driver");
this.url = props.getProperty("url");
this.user = props.getProperty("user");
this.password = props.getProperty("password");
}
//implement the Connection
private void setConn(){
try {
Class.forName(driver);
this.conn = DriverManager.getConnection(url,user,password);
} catch(ClassNotFoundException classnotfoundexception) {
classnotfoundexception.printStackTrace();
System.err.println("db: " + classnotfoundexception.getMessage());
} catch(SQLException sqlexception) {
System.err.println("db.getconn(): " + sqlexception.getMessage());
}
}
public void doInsert(String sql) {
try {
Statement statement = conn.createStatement();
int i = stm.executeUpdate(sql);
} catch(SQLException sqlexception) {
System.err.println("db.executeInset:" + sqlexception.getMessage());
}
}
public void doDelete(String sql) {
try {
stm = conn.createStatement();
int i = stm.executeUpdate(sql);
} catch(SQLException sqlexception) {
System.err.println("db.executeDelete:" + sqlexception.getMessage());
}
}
public void doUpdate(String sql) {
try {
stm = conn.createStatement();
int i = stm.executeUpdate(sql);
} catch(SQLException sqlexception) {
System.err.println("db.executeUpdate:" + sqlexception.getMessage());
}
}

public ResultSet doSelect(String sql) {
try {
stm = conn.createStatement(java.sql.ResultSet.TYPE_SCROLL_INSENSITIVE,java.sql.ResultSet.CONCUR_READ_ONLY);
rs = stm.executeQuery(sql);
} catch(SQLException sqlexception) {
System.err.println("db.executeQuery: " + sqlexception.getMessage());
}
return rs;
}
public static void main(String[] args){
try{
Db db = new Db();
Connection conn = db.getConn();
if(conn != null && !conn.isClosed()) {
System.out.println("連結成功");
ResultSet rs = db.doSelect("select * from content");
while(rs.next()){
System.out.println(rs.getString(1)+":"+rs.getString(2)+":"+rs.getString(3));
}
rs.close();
conn.close();
}
}catch(SQLException e) {
e.printStackTrace();
}
}
}

DBConf.properties:
driver=oracle.jdbc.driver.OracleDriver
url=jdbc:oracle:thin:@tdt151:1521:train
user=XX
password=XX

/**
* 人民币转成大写
*
* @param value
* @return String
*/
public static String hangeToBig(double value)
{
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
}

public static String getURLByDBInfo(DBInfo dbInfo)
{
String url = "";
if(dbInfo.getDbType() != null)
if(dbInfo.getDbType().equals("SQLSERVER"))
url = (new StringBuilder("jdbc:microsoft:sqlserver://")).append(dbInfo.getDbHost()).append(":").append(dbInfo.getDbPort()).append(";DatabaseName=").append(dbInfo.getDbSID()).toString();
else
if(dbInfo.getDbType().equals("ORACLE"))
url = (new StringBuilder("jdbc:oracle:thin:@")).append(dbInfo.getDbHost()).append(":").append(dbInfo.getDbPort()).append(":").append(dbInfo.getDbSID()).toString();
else
if(dbInfo.getDbType().equals("ORACLE_DSP"))
url = (new StringBuilder("jdbc:dsp@")).append(dbInfo.getDbHost()).append(":").append(dbInfo.getDbPort()).append("/").append(dbInfo.getDbSID()).append("/").append(dbInfo.getNamespace()).toString();
else
if(dbInfo.getDbType().equals("SYBASE"))
url = "jdbc:sybase:Tds:";
else
url = "sun.jdbc.odbc.JdbcOdbcDriver";
return url;
}

/**
* 全角字符转半角字符
*
* @param QJStr
* @return String
*/
public static final String QJToBJChange(String QJStr)
{
char[] chr = QJStr.toCharArray();
String str = "";
for (int i = 0; i < chr.length; i++)
{
chr[i] = (char) ((int) chr[i] - 65248);
str += chr[i];
}
return str;
}

/**
* 去掉字符串中重复的子字符串
*
* @param str
* @return String
*/
private static String removeSameString(String str)
{
Set<String> mLinkedSet = new LinkedHashSet<String>();
String[] strArray = str.split(" ");
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().substring(0, sb.toString().length() - 1);
}

/**
* 设置JSpinner的编辑属性
* @param spinner 目标JSpinner
* @param isAllowInvalid 是否允许输入非法值
* @param isEditable 是否允许编辑
*/
public static void setAllowsInvalid(JSpinner spinner, boolean isAllowInvalid, boolean isEditable)
{
JSpinner.NumberEditor editor = new JSpinner.NumberEditor(spinner, "#");
spinner.setEditor(editor);
JFormattedTextField tf = ((JSpinner.NumberEditor)spinner.getEditor()).getTextField();
tf.setEditable(isEditable);
DefaultFormatterFactory factory = (DefaultFormatterFactory)tf.getFormatterFactory();
NumberFormatter formatter = (NumberFormatter)factory.getDefaultFormatter();
formatter.setAllowsInvalid(isAllowInvalid);
}

/**
* 根据指定方法的参数去构造一个新的对象的拷贝并将他返回
* @param obj 原始对象
* @return 新对象
* @throws NoSuchMethodException
* @throws InvocationTargetException
* @throws IllegalAccessException
* @throws InstantiationException
* @throws SecurityException
* @throws IllegalArgumentException
*/
@SuppressWarnings("unchecked")
public static Object copy(Object obj) throws IllegalArgumentException, SecurityException, InstantiationException, IllegalAccessException,
InvocationTargetException, NoSuchMethodException
{
//获得对象的类型
Class classType = obj.getClass();

//通过默认构造方法去创建一个新的对象，getConstructor的视其参数决定调用哪个构造方法
Object objectCopy = classType.getConstructor(new Class[]{}).newInstance(new Object[]{});

//获得对象的所有属性
Field[] fields = classType.getDeclaredFields();

for(int i = 0; i < fields.length; i++)
{
//获取数组中对应的属性
Field field = fields[i];

String fieldName = field.getName();
String stringLetter = fieldName.substring(0, 1).toUpperCase();

//获得相应属性的getXXX和setXXX方法名称
String getName = "get" + stringLetter + fieldName.substring(1);
String setName = "set" + stringLetter + fieldName.substring(1);

//获取相应的方法
Method getMethod = classType.getMethod(getName, new Class[]{});
Method setMethod = classType.getMethod(setName, new Class[]{field.getType()});

//调用源对象的getXXX（）方法
Object value = getMethod.invoke(obj, new Object[]{});

//调用拷贝对象的setXXX（）方法
setMethod.invoke(objectCopy, new Object[]{value});
}

return objectCopy;
}

//过滤特殊字符
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();
}

//反过滤特殊字符
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;
}

//利用反射调用一个继承层次上的函数族，比如安装程序，有安装数据库的，安装文件系统的等，命名均已“install”开始，你就可以将参数part设为“install”，src是其实类实例，root是终止父类
public static <T> void invokeMethods(String part,T src,Class root) throws ExceptionManager{
if (root!=null){
if (!root.isInstance(src))return;
root=(Class)root.getGenericSuperclass();
}
HashMap<String,Method> invokees=new HashMap<String,Method>();
Class target=src.getClass();
do{
Method [] methods=target.getDeclaredMethods();
for (Method method:methods){
String mn=method.getName();
Boolean isPass=mn.startsWith(part);
if (isPass){
Integer nopt=method.getParameterTypes().length;
Boolean isStatic=Modifier.isStatic(method.getModifiers());
if ((nopt==0)&&(!isStatic)){
if (!invokees.containsKey(mn))
invokees.put(mn, method);
}
}
}
target=(Class)target.getGenericSuperclass();
}while(target!=root);
Iterator<String> methods=invokees.keySet().iterator();
while (methods.hasNext()){
Method invokee=invokees.get(methods.next());
Boolean access=invokee.isAccessible();
invokee.setAccessible(true);
try {
invokee.invoke(src);
} catch (InvocationTargetException e) {
throw ExceptionManager.wrap(e.getTargetException());
}catch (Exception e){}
invokee.setAccessible(access);
}
}

MySQL：
String Driver="com.mysql.jdbc.Driver"; //驱动程序
String URL="jdbc:mysql://localhost:3306/db_name"; //连接的URL,db_name为数据库名
String Username="username"; //用户名
String Password="password"; //密码
Class.forName(Driver).new Instance();
Connection con=DriverManager.getConnection(URL,Username,Password);
Microsoft SQL Server 2.0驱动(3个jar的那个):
String Driver="com.microsoft.jdbc.sqlserver.SQLServerDriver"; //连接SQL数据库的方法
String URL="jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=db_name"; //db_name为数据库名
String Username="username"; //用户名
String Password="password"; //密码
Class.forName(Driver).new Instance(); //加载数据可驱动
Connection con=DriverManager.getConnection(URL,UserName,Password); //
Microsoft SQL Server 3.0驱动(1个jar的那个): // 老紫竹完善
String Driver="com.microsoft.sqlserver.jdbc.SQLServerDriver"; //连接SQL数据库的方法
String URL="jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=db_name"; //db_name为数据库名
String Username="username"; //用户名
String Password="password"; //密码
Class.forName(Driver).new Instance(); //加载数据可驱动
Connection con=DriverManager.getConnection(URL,UserName,Password); //
Sysbase:
String Driver="com.sybase.jdbc.SybDriver"; //驱动程序
String URL="jdbc:Sysbase://localhost:5007/db_name"; //db_name为数据可名
String Username="username"; //用户名
String Password="password"; //密码
Class.forName(Driver).newInstance();
Connection con=DriverManager.getConnection(URL,Username,Password);
Oracle(用thin模式):
String Driver="oracle.jdbc.driver.OracleDriver"; //连接数据库的方法
String URL="jdbc:oracle:thin:@loaclhost:1521:orcl"; //orcl为数据库的SID
String Username="username"; //用户名
String Password="password"; //密码
Class.forName(Driver).newInstance(); //加载数据库驱动
Connection con=DriverManager.getConnection(URL,Username,Password);
PostgreSQL:
String Driver="org.postgresql.Driver"; //连接数据库的方法
String URL="jdbc:postgresql://localhost/db_name"; //db_name为数据可名
String Username="username"; //用户名
String Password="password"; //密码
Class.forName(Driver).newInstance();
Connection con=DriverManager.getConnection(URL,Username,Password);
DB2：
String Driver="com.ibm.db2.jdbc.app.DB2.Driver"; //连接具有DB2客户端的Provider实例
//String Driver="com.ibm.db2.jdbc.net.DB2.Driver"; //连接不具有DB2客户端的Provider实例
String URL="jdbc:db2://localhost:5000/db_name"; //db_name为数据可名
String Username="username"; //用户名
String Password="password"; //密码
Class.forName(Driver).newInstance();
Connection con=DriverManager.getConnection(URL,Username,Password);
Informix:
String Driver="com.informix.jdbc.IfxDriver";
String URL="jdbc:Informix-sqli://localhost:1533/db_name:INFORMIXSER=myserver"; //db_name为数据可名
String Username="username"; //用户名
String Password="password"; //密码
Class.forName(Driver).newInstance();
Connection con=DriverManager.getConnection(URL,Username,Password);
JDBC-ODBC:
String Driver="sun.jdbc.odbc.JdbcOdbcDriver";
String URL="jdbc:odbc:dbsource"; //dbsource为数据源名
String Username="username"; //用户名
String Password="password"; //密码
Class.forName(Driver).newInstance();
Connection con=DriverManager.getConnection(URL,Username,Password);

import java.text.DecimalFormat;

public class NumberUtil {

public static double decimalFormatD(int num, double d){
String format = "0.";
String result = "";
double db;

for(int i=0;i<num;i++)
format = format.concat("0");

DecimalFormat decimal = new DecimalFormat(format);
result = decimal.format(d);
db = Double.parseDouble(result);

return db;
}

public static float decimalFormatF(int num, float f){
String format = "0.";
String result = "";
float fl;

for(int i=0;i<num;i++)
format = format.concat("0");

DecimalFormat decimal = new DecimalFormat(format);
result = decimal.format(f);
fl = Float.parseFloat(result);

return fl;
}

public static String doubleToString(double f){
String s = "";
double a = 0;

while(f >= 1) {

a = f%((double)10);

s = String.valueOf((int)a) + s;
f=(f - a)/10;
}
return s;
}
}

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.util.StringTokenizer;

public class TxtToXml {
private String strTxtFileName;

private String strXmlFileName;

public TxtToXml() {
strTxtFileName = new String();
strXmlFileName = new String();
}

public void createXml(String strTxt, String strXml) {
strTxtFileName = strTxt;
strXmlFileName = strXml;
String strTmp;
try {
BufferedReader inTxt = new BufferedReader(new FileReader(
strTxtFileName));
BufferedWriter outXml = new BufferedWriter(new FileWriter(
strXmlFileName));
outXml.write("<?xml version= \"1.0\" encoding=\"gb2312\"?>");
outXml.newLine();
outXml.write("<people>");
while ((strTmp = inTxt.readLine()) != null) {
StringTokenizer strToken = new StringTokenizer(strTmp, "，");
String arrTmp[];
arrTmp = new String[3];
for (int i = 0; i < 3; i++)
arrTmp[i] = new String("");
int index = 0;
outXml.newLine();
outXml.write(" <students>");
while (strToken.hasMoreElements()) {
strTmp = (String) strToken.nextElement();
strTmp = strTmp.trim();
arrTmp[index++] = strTmp;
}
outXml.newLine();
outXml.write(" <name>" + arrTmp[0] + "</name>");
outXml.newLine();
outXml.write(" <sex>" + arrTmp[1] + "</sex>");
outXml.newLine();
outXml.write(" <age>" + arrTmp[2] + "</age>");
outXml.newLine();
outXml.write(" </students>");
}
outXml.newLine();
outXml.write("</people>");
outXml.flush();
} catch (Exception e) {
e.printStackTrace();
}
}

public static void main(String[] args) {
String txtName = "testtxt.txt";
String xmlName = "testxml.xml";
TxtToXml thisClass = new TxtToXml();
thisClass.createXml(txtName, xmlName);
}
}

/**
* 写入日志
* filePath 日志文件的路径
* code 要写入日志文件的内容
*/
public static boolean print(String filePath,String code) {
try {
File tofile=new File(filePath);
FileWriter fw=new FileWriter(tofile,true);
BufferedWriter bw=new BufferedWriter(fw);
PrintWriter pw=new PrintWriter(bw);

System.out.println(getDate()+":"+code);
pw.println(getDate()+":"+code);
pw.close();
bw.close();
fw.close();
return true;
} catch (IOException e) {
return false;
}
}

/**
* 判断是不是合法手机
* handset 手机号码
*/
public static boolean isHandset(String handset) {
try {
if(!handset.substring(0,1).equals("1")) {
return false;
}
if (handset==null || handset.length()!=11) {
return false;
}
String check = "^[0123456789]+$";
Pattern regex = Pattern.compile(check);
Matcher matcher = regex.matcher(handset);
boolean isMatched = matcher.matches();
if(isMatched) {
return true;
} else {
return false;
}
} catch (RuntimeException e) {
return false;
}
}
}

字符串匹配的算法.
public String getMaxMatch(String a,String b) {
StringBuffer tmp = new StringBuffer();
String maxString = "";
int max = 0;
int len = 0;
char[] aArray = a.toCharArray();
char[] bArray = b.toCharArray();
int posA = 0;
int posB = 0;
while(posA<aArray.length-max) {
posB = 0;
while(posB<(bArray.length-max)) {
if(aArray[posA]==bArray[posB]) {
len = 1;
tmp = new StringBuffer();
tmp.append(aArray[posA]);
while((posA+len<aArray.length)&&(posB+len<bArray.length)&&(aArray[posA+len]==bArray[posB+len])) {
tmp.append(aArray[posA+len]);
len++;
}
if(len>max) {
max = len;
maxString = tmp.toString();
}
}
posB++;
}
posA++;
}
return maxString;
}

import java.text.DecimalFormat;
import java.util.Arrays;

/**
* 时间计算工具类
*/
public class Time {

/**
* 时间字段常量，表示“秒”
*/
public final static int SECOND = 0;

/**
* 时间字段常量，表示“分”
*/
public final static int MINUTE = 1;

/**
* 时间字段常量，表示“时”
*/
public final static int HOUR = 2;

/**
* 时间字段常量，表示“天”
*/
public final static int DAY = 3;

/**
* 各常量允许的最大值
*/
private final int[] maxFields = { 59, 59, 23, Integer.MAX_VALUE - 1 };

/**
* 各常量允许的最小值
*/
private final int[] minFields = { 0, 0, 0, Integer.MIN_VALUE };

/**
* 默认的字符串格式时间分隔符
*/
private String timeSeparator = ":";

/**
* 时间数据容器
*/
private int[] fields = new int[4];

/**
* 无参构造，将各字段置为 0
*/
public Time() {
this(0, 0, 0, 0);
}

/**
* 使用时、分构造一个时间
* @param hour 小时
* @param minute 分钟
*/
public Time(int hour, int minute) {
this(0, hour, minute, 0);
}

/**
* 使用时、分、秒构造一个时间
* @param hour 小时
* @param minute 分钟
* @param second 秒
*/
public Time(int hour, int minute, int second) {
this(0, hour, minute, second);
}

/**
* 使用一个字符串构造时间<br/>
* Time time = new Time("14:22:23");
* @param time 字符串格式的时间，默认采用“:”作为分隔符
*/
public Time(String time) {
this(time, null);
}

/**
* 使用天、时、分、秒构造时间，进行全字符的构造
* @param day 天
* @param hour 时
* @param minute 分
* @param second 秒
*/
public Time(int day, int hour, int minute, int second) {
set(DAY, day);
set(HOUR, hour);
set(MINUTE, minute);
set(SECOND, second);
}

/**
* 使用一个字符串构造时间，指定分隔符<br/>
* Time time = new Time("14-22-23", "-");
* @param time 字符串格式的时间
*/
public Time(String time, String timeSeparator) {
if(timeSeparator != null) {
setTimeSeparator(timeSeparator);
}
String pattern = patternQuote(this.timeSeparator);
String matcher = new StringBuffer()
.append("\\d+?").append(pattern)
.append("\\d+?").append(pattern)
.append("\\d+?")
.toString();
if(!time.matches(matcher)) {
throw new IllegalArgumentException(time + ", time format error, HH"
+ this.timeSeparator + "mm" + this.timeSeparator + "ss");
}
String[] times = time.split(pattern);
set(DAY, 0);
set(HOUR, Integer.parseInt(times[0]));
set(MINUTE, Integer.parseInt(times[1]));
set(SECOND, Integer.parseInt(times[2]));
}

/**
* 设置时间字段的值
* @param field 时间字段常量
* @param value 时间字段的值
*/
public void set(int field, int value) {
if(value < minFields[field]) {
throw new IllegalArgumentException(value +
", time value must be positive.");
}
fields[field] = value % (maxFields[field] + 1);
// 进行进位计算
int carry = value / (maxFields[field] + 1);
if(carry > 0) {
int upFieldValue = get(field + 1);
set(field + 1, upFieldValue + carry);
}
}

/**
* 获得时间字段的值
* @param field 时间字段常量
* @return 该时间字段的值
*/
public int get(int field) {
if(field < 0 || field > fields.length - 1) {
throw new IllegalArgumentException(field + ", field value is error.");
}
return fields[field];
}

/**
* 将时间进行“加”运算，即加上一个时间
* @param time 需要加的时间
* @return 运算后的时间
*/
public Time addTime(Time time) {
Time result = new Time();
int up = 0; // 进位标志
for (int i = 0; i < fields.length; i++) {
int sum = fields[i] + time.fields[i] + up;
up = sum / (maxFields[i] + 1);
result.fields[i] = sum % (maxFields[i] + 1);
}
return result;
}

/**
* 将时间进行“减”运算，即减去一个时间
* @param time 需要减的时间
* @return 运算后的时间
*/
public Time subtractTime(Time time) {
Time result = new Time();
int down = 0; // 退位标志
for (int i = 0, k = fields.length - 1; i < k; i++) {
int difference = fields[i] + down;
if (difference >= time.fields[i]) {
difference -= time.fields[i];
down = 0;
} else {
difference += maxFields[i] + 1 - time.fields[i];
down = -1;
}
result.fields[i] = difference;
}
result.fields[DAY] = fields[DAY] - time.fields[DAY] + down;
return result;
}

/**
* 获得时间字段的分隔符
* @return
*/
public String getTimeSeparator() {
return timeSeparator;
}

/**
* 设置时间字段的分隔符（用于字符串格式的时间）
* @param timeSeparator 分隔符字符串
*/
public void setTimeSeparator(String timeSeparator) {
this.timeSeparator = timeSeparator;
}

/**
* 正则表达式引用处理方法，源自 JDK @link java.util.regex.Pattern#quote(String)
*/
private String patternQuote(String s) {
int slashEIndex = s.indexOf("\\E");
if (slashEIndex == -1)
return "\\Q" + s + "\\E";

StringBuilder sb = new StringBuilder(s.length() * 2);
sb.append("\\Q");
slashEIndex = 0;
int current = 0;
while ((slashEIndex = s.indexOf("\\E", current)) != -1) {
sb.append(s.substring(current, slashEIndex));
current = slashEIndex + 2;
sb.append("\\E\\\\E\\Q");
}
sb.append(s.substring(current, s.length()));
sb.append("\\E");
return sb.toString();
}

public String toString() {
DecimalFormat df = new DecimalFormat("00");
return new StringBuffer().append(fields[DAY]).append(", ")
.append(df.format(fields[HOUR])).append(timeSeparator)
.append(df.format(fields[MINUTE])).append(timeSeparator)
.append(df.format(fields[SECOND]))
.toString();
}

public int hashCode() {
final int PRIME = 31;
int result = 1;
result = PRIME * result + Arrays.hashCode(fields);
return result;
}

public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
final Time other = (Time) obj;
if (!Arrays.equals(fields, other.fields)) {
return false;
}
return true;
}
}