Java 从字符串解析日期/时间?
我试图创建一个程序来解析字符串中有意义的日期和时间。我希望能够提供以下类型的输入,并创建日期/时间对象:Java 从字符串解析日期/时间?,java,string,parsing,date,time,Java,String,Parsing,Date,Time,我试图创建一个程序来解析字符串中有意义的日期和时间。我希望能够提供以下类型的输入,并创建日期/时间对象: 5 o'clock 5 p.m. 5 a.m. 5 530 530 a.m. 530 p.m. Tuesday at [insert any above string here] the 30th at [same as above] May 12th at [same as above] today at [same as above] tomorrow at [same as above
5 o'clock
5 p.m.
5 a.m.
5
530
530 a.m.
530 p.m.
Tuesday at [insert any above string here]
the 30th at [same as above]
May 12th at [same as above]
today at [same as above]
tomorrow at [same as above]
任何不包含日期的字符串都可以假定为今天,任何没有AM/PM名称的时间都可以假定为发生在上午9点到晚上8:59之间。
在编写了这部分代码后,我很快意识到这是多么混乱:
private void createEvent(String phrase) {
int hour;
int day = 0;
String dayOfWeek = "";
if (phrase.contains("o'clock")) {
hour = Integer.parseInt(phrase.substring(phrase.indexOf("o'clock")-3, phrase.indexOf("o'clock")-1).trim());
out.write(""+hour);
}
if (phrase.contains("tomorrow"))
day = (Calendar.DAY_OF_WEEK % 7)+1;
if (phrase.contains("sunday") || day == 1) {
dayOfWeek = "Sunday"; day = 1; }
else if (phrase.contains("monday") || day == 2) {
dayOfWeek = "Monday"; day = 2; }
else if (phrase.contains("tuesday") || day == 3) {
dayOfWeek = "Tuesday"; day = 3; }
else if (phrase.contains("wednesday") || day == 4) {
dayOfWeek = "Wednesday"; day = 4; }
else if (phrase.contains("thursday") || day == 5) {
dayOfWeek = "Thursday"; day = 5; }
else if (phrase.contains("friday") || day == 6) {
dayOfWeek = "Friday"; day = 6; }
else if (phrase.contains("saturday") || day == 7) {
dayOfWeek = "Saturday"; day = 7; }
else {
dayOfWeek = "Today"; day = 0; }
}
有人能提供一些指导吗?您可以使用DateFormat
String now = new Date().toString();
SimpleDateFormat format = new SimpleDateFormat("EEE MMM dd HH:mm:ss zzz yyyy");
Date date = format.parse(now);
也许你可以提前构建一些格式,然后比较解析的日期
检查此处的教程:您可以使用DateFormat
String now = new Date().toString();
SimpleDateFormat format = new SimpleDateFormat("EEE MMM dd HH:mm:ss zzz yyyy");
Date date = format.parse(now);
也许你可以提前构建一些格式,然后比较解析的日期
查看此处的教程:将问题分解为可管理的部分 首先,我将提供一种方法,您可以根据需要添加新的格式化程序 我也会尝试重新使用现有的代码。对于你的问题来说,时间是一个相当一致的方面 这将使我想到提供某种集中格式工厂的概念(使管理更容易),但将单个需求分解为更小的可管理块
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Calendar;
import java.util.Date;
import java.util.List;
public class CustomDateFormatter {
public static void main(String[] args) {
new CustomDateFormatter();
}
public CustomDateFormatter() {
String values[] = new String[]{
"5 o'clock",
"5 p.m.",
"5 a.m.",
"5",
"530",
"530 a.m.",
"530 p.m.",};
for (String value : values) {
System.out.println(value + " = " + CustomFormatFactory.format(value));
}
}
public static class CustomFormatFactory {
private static List<CustomFormat> formatters = new ArrayList<>();
public static Date format(String value) {
Date date = null;
for (CustomFormat format : formatters) {
if (format.canFormat(value)) {
date = format.format(value);
if (date != null) {
break;
}
}
}
return date;
}
protected static boolean formatTime(String value, Calendar cal) {
boolean formatted = false;
if (Character.isDigit(value.charAt(0))) {
formatted = true;
StringBuilder timePart = new StringBuilder(4);
int index = 0;
while (index < value.length() && Character.isDigit(value.charAt(index))) {
timePart.append(value.charAt(index));
index++;
}
int hour = 0;
int min = 0;
if (timePart.length() < 3) {
hour = Integer.parseInt(timePart.toString());
} else {
hour = Integer.parseInt(timePart.substring(0, timePart.length() - 2));
min = Integer.parseInt(timePart.substring(timePart.length() - 2, 3));
}
cal.set(Calendar.HOUR_OF_DAY, hour);
cal.set(Calendar.MINUTE, min);
cal.set(Calendar.MILLISECOND, 0);
String sufix = value.substring(timePart.length()).trim();
if ("p.m.".equalsIgnoreCase(sufix) || "pm".equalsIgnoreCase(sufix)) {
cal.add(Calendar.HOUR, 12);
}
}
return formatted;
}
static {
formatters.add(new SimpleTimeFormat());
}
}
public static interface CustomFormat {
public boolean canFormat(String value);
public Date format(String value);
}
public static class SimpleTimeFormat implements CustomFormat {
@Override
public boolean canFormat(String value) {
return format(value) != null;
}
@Override
public Date format(String value) {
Date date = null;
Calendar cal = Calendar.getInstance();
if (CustomFormatFactory.formatTime(value, cal)) {
date = cal.getTime();
}
return date;
}
}
}
import java.util.ArrayList;
导入java.util.array;
导入java.util.Calendar;
导入java.util.Date;
导入java.util.List;
公共类CustomDateFormatter{
公共静态void main(字符串[]args){
新的CustomDateFormatter();
}
公共CustomDateFormatter(){
字符串值[]=新字符串[]{
“5点钟”,
“下午5点”,
“早上5点”,
"5",
"530",
“早上530点”,
“下午530时”,};
for(字符串值:值){
System.out.println(值+“=”+CustomFormatFactory.format(值));
}
}
公共静态类CustomFormatFactory{
私有静态列表格式化程序=新的ArrayList();
公共静态日期格式(字符串值){
日期=空;
用于(自定义格式:格式化程序){
if(format.canFormat(value)){
日期=格式。格式(值);
如果(日期!=null){
打破
}
}
}
返回日期;
}
受保护的静态布尔格式时间(字符串值、日历校准){
布尔格式=假;
if(Character.isDigit(value.charAt(0))){
格式化=真;
StringBuilder timePart=新StringBuilder(4);
int指数=0;
while(index
对于扩展的日期格式,我将提取日期部分,基于日期构建一个日历
,将时间分区提取为一个单独的字符串
,并使用CustomFormatFactory.formatTime
方法来格式化时间,这样就省去了每次重新编码的麻烦
同样,日期格式化程序可以简单地在内部具有时间格式化程序的实例,或者您可以将工厂设置为具有多个格式化方法,其中一个方法接受时间值并循环使用可用的时间格式化程序。。。这将是我个人的选择;) 将您的问题分解为可管理的部分 首先,我将提供一种方法,您可以根据需要添加新的格式化程序 我也会尝试重新使用现有的代码。对于你的问题来说,时间是一个相当一致的方面 这将使我想到提供某种集中格式工厂的概念(使管理更容易),但将单个需求分解为更小的可管理块
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Calendar;
import java.util.Date;
import java.util.List;
public class CustomDateFormatter {
public static void main(String[] args) {
new CustomDateFormatter();
}
public CustomDateFormatter() {
String values[] = new String[]{
"5 o'clock",
"5 p.m.",
"5 a.m.",
"5",
"530",
"530 a.m.",
"530 p.m.",};
for (String value : values) {
System.out.println(value + " = " + CustomFormatFactory.format(value));
}
}
public static class CustomFormatFactory {
private static List<CustomFormat> formatters = new ArrayList<>();
public static Date format(String value) {
Date date = null;
for (CustomFormat format : formatters) {
if (format.canFormat(value)) {
date = format.format(value);
if (date != null) {
break;
}
}
}
return date;
}
protected static boolean formatTime(String value, Calendar cal) {
boolean formatted = false;
if (Character.isDigit(value.charAt(0))) {
formatted = true;
StringBuilder timePart = new StringBuilder(4);
int index = 0;
while (index < value.length() && Character.isDigit(value.charAt(index))) {
timePart.append(value.charAt(index));
index++;
}
int hour = 0;
int min = 0;
if (timePart.length() < 3) {
hour = Integer.parseInt(timePart.toString());
} else {
hour = Integer.parseInt(timePart.substring(0, timePart.length() - 2));
min = Integer.parseInt(timePart.substring(timePart.length() - 2, 3));
}
cal.set(Calendar.HOUR_OF_DAY, hour);
cal.set(Calendar.MINUTE, min);
cal.set(Calendar.MILLISECOND, 0);
String sufix = value.substring(timePart.length()).trim();
if ("p.m.".equalsIgnoreCase(sufix) || "pm".equalsIgnoreCase(sufix)) {
cal.add(Calendar.HOUR, 12);
}
}
return formatted;
}
static {
formatters.add(new SimpleTimeFormat());
}
}
public static interface CustomFormat {
public boolean canFormat(String value);
public Date format(String value);
}
public static class SimpleTimeFormat implements CustomFormat {
@Override
public boolean canFormat(String value) {
return format(value) != null;
}
@Override
public Date format(String value) {
Date date = null;
Calendar cal = Calendar.getInstance();
if (CustomFormatFactory.formatTime(value, cal)) {
date = cal.getTime();
}
return date;
}
}
}
import java.util.ArrayList;
导入java.util.array;
导入java.util.Calendar;
导入java.util.Date;
导入java.util.List;
公共类CustomDateFormatter{
公共静态void main(字符串[]args){
新的CustomDateFormatter();
}
公共CustomDateFormatter(){
字符串值[]=新字符串[]{
“5点钟”,
“下午5点”,
“早上5点”,
"5",
"530",
“早上530点”,
“下午530时”,};
对于(字符串值: