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u014689192：
很不错
JMX学习笔记(三)-MXBean -
focus2008：
进制转换之后，根本不会执行js代码，感觉你没有测试过吧
xss漏洞之进制转换 -
focus2008：
如何使用过滤器来处理呢？
xss漏洞之进制转换 -
1169158401：
我艹，我那天这么写，包括一些方法，然后那货说这样写不容易看懂。 ...
import static简化代码 -
AquariusM：
奢华的JVM介绍！
JMX学习笔记(三)-MXBean
以前写过一篇 , 《SimpleDateFormat性能调优》http://tuhaitao.iteye.com/admin/blogs/822277
虽然可以解决SimpleDateFormat的线程安全问题，但不能够灵活的配置日期Parten，为了使其能够灵活的配置日期格式，我进行了一番改造。
1. 通过配置文件加载Praten，灵活配置日期格式
2. 使用FastHashMap结合ThreadLocal，解决多个日期格式的线程安全问题
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.opencfg.core;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import org.apache.commons.collections.FastHashMap;
import org.apache.commons.lang.StringUtils;
/**
* <p>
* DateFormat Utils
* <p>
*
* <p>#ThreadSafe#</p>
*
* @author Opencfg Software Foundation
* @since 0.0.1-SNAPSHOT
* @version $Id: DateFormatUtils.java 2011-06-14 23:21:53 reymondtu $
*/
public class DateFormatUtils {
private static final FastHashMap datePartenMap = new FastHashMap();
static {
// load data parten properties files
List<String> propList = PropertiesUtils.getSimpleList("DateFormatUtils.properties") ;
datePartenMap.setFast(true);
for(String dateParten : propList) {
if(StringUtils.startsWith(dateParten, "#")) continue;
datePartenMap.put(StringUtils.trim(dateParten), new SimpleDateFormat(dateParten));
}
}
/**
* String -> Date
*
* @param dateParten Parse Date Parten
* @param dateStr Parse Date String
* @throws ParseException
*/
public static Date safeParseDate(final String dateParten, final String dateStr) throws ParseException {
return getFormat(dateParten).parse(dateStr);
}
/**
* Date -> String
*
* @param dateParten Format Date Parten
* @param date Format java.util.Date Object
*/
public static String safeFormatDate(final String dateParten, final Date date) {
return getFormat(dateParten).format(date);
}
private static ThreadLocal<FastHashMap> threadLocal = new ThreadLocal<FastHashMap>(){
protected synchronized FastHashMap initialValue() {
return (FastHashMap)datePartenMap.clone();
}
};
private static DateFormat getFormat(final String dateParten){
return (DateFormat)threadLocal.get().get(dateParten);
}
}
这里使用了apache commons-collections里的FashHashMap类，此类适用于读多写少的高并发操作，很适合写缓存.
下边是读取配置文件的类:
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.opencfg.core;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import org.apache.commons.configuration.ConfigurationException;
import org.apache.commons.configuration.PropertiesConfiguration;
import org.apache.commons.configuration.reloading.FileChangedReloadingStrategy;
import org.apache.commons.lang.StringUtils;
/**
* <p>
* Properties Utils
* <p>
*
* <p>#ThreadSafe#</p>
*
* @author Opencfg Software Foundation
* @since 0.0.1-SNAPSHOT
* @version $Id: PropertiesUtils.java 2011-06-15 01:22:53 reymondtu $
*/
public class PropertiesUtils {
/**
* Load Properties File
* @throws ConfigurationException
*/
public static PropertiesConfiguration loadClassPathProperties(final String fileName, final long refreshInterval) throws ConfigurationException {
URL url = PropertiesUtils.class.getClassLoader().getResource(fileName);
File f = new File(url.getFile());
if(!f.exists()) {
throw new IllegalArgumentException("can not load file " + fileName);
}
PropertiesConfiguration prop = new PropertiesConfiguration(url.getFile());
FileChangedReloadingStrategy fcrs = null;
fcrs = new FileChangedReloadingStrategy();
fcrs.setRefreshDelay(refreshInterval);
prop.setReloadingStrategy(fcrs);
return prop;
}
public static List<String> getSimpleList(final String fileName) {
try {
PropertiesConfiguration prop = loadClassPathProperties(fileName, 500);
BufferedReader reader = new BufferedReader(new FileReader(prop.getFile()));
List<String> list = new ArrayList<String>();
String line = null;
while ((line =reader.readLine())!= null) {
if(StringUtils.startsWith(line, "#")) {
continue;
}
list.add(line);
line = reader.readLine();
}
return list;
} catch (Exception e) {
throw new IllegalArgumentException("can not load file " + fileName);
}
}
}
配置文件DateFormatUtils.properties如下：
#show all yyyy-MM-dd HH:mm:ss yyyy年MM月dd日 HH:mm:ss yyyy年MM月dd日 HH时mm分ss秒 #only show date yyyy-MM-dd yyyy年MM月dd日 #only show hour,minute,second HH:mm:ss HH时mm分ss秒
这里我跟传统的SimpleDateFormat，apache 的 FastDateForma, DateUtilst做了性能对比：
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.opencfg.core;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import org.apache.commons.lang.time.FastDateFormat;
import org.junit.Before;
import org.junit.Test;
/**
* DateFormatUtils JUnit4 Test
*
* @author Opencfg Software Foundation
* @since 0.0.1-SNAPSHOT
* @version $Id: DateFormatUtilsTest.java 2011-06-15 00:36:53 reymondtu $
*/
public class DateFormatUtilsTest {
private final int TEST_SIZE = 1000000;
private Date[] dateArray = new Date[TEST_SIZE];
private String[] stringArray = new String[TEST_SIZE];
@Before
public void setUp() {
for(int i = 0; i < TEST_SIZE; i++) {
dateArray[i] = new Date();
}
for(int i = 0; i < TEST_SIZE; i++) {
stringArray[i] = DateFormatUtils.safeFormatDate("yyyy-MM-dd HH:mm:ss", new Date());
}
}
/* Format */
@Test
public void test_JDK_SimpleDateFormat_format() {
long starttime = System.currentTimeMillis();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
for(Date date : dateArray) {
sdf.format(date);
}
long endtime = System.currentTimeMillis();
System.out.println("JDK SimpleDateFormat format cost:" + (endtime - starttime) + "ms");
}
@Test
public void test_Opencfg_DateFormatUtils_format() {
long starttime = System.currentTimeMillis();
for(Date date : dateArray) {
DateFormatUtils.safeFormatDate("yyyy-MM-dd HH:mm:ss", date);
}
long endtime = System.currentTimeMillis();
System.out.println("Opencfg DateFormatUtils format cost:" + (endtime - starttime) + "ms");
}
@Test
public void test_Apache_FastDateFormat_format() {
FastDateFormat fastDateFormat = FastDateFormat.getInstance();
long starttime = System.currentTimeMillis();
for(Date date : dateArray) {
fastDateFormat.format(date);
}
long endtime = System.currentTimeMillis();
System.out.println("Apache FastDateFormat format cost:" + (endtime - starttime) + "ms");
}
/* Parse */
@Test
public void test_JDK_SimpleDateFormat_parse() throws ParseException {
long starttime = System.currentTimeMillis();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
for(String str : stringArray) {
sdf.parse(str);
}
long endtime = System.currentTimeMillis();
System.out.println("JDK SimpleDateFormat parse cost:" + (endtime - starttime) + "ms");
}
@Test
public void test_Opencfg_DateFormatUtils_parse() throws ParseException {
long starttime = System.currentTimeMillis();
for(String str : stringArray) {
DateFormatUtils.safeParseDate("yyyy-MM-dd HH:mm:ss", str);
}
long endtime = System.currentTimeMillis();
System.out.println("Opencfg DateFormatUtils parse cost:" + (endtime - starttime) + "ms");
}
@Test
public void test_Apache_DateUtils_parse() throws ParseException {
long starttime = System.currentTimeMillis();
String[] dateParten = new String[]{"yyyy-MM-dd HH:mm:ss"};
for(String str : stringArray) {
org.apache.commons.lang.time.DateUtils.parseDate(str, dateParten);
}
long endtime = System.currentTimeMillis();
System.out.println("Apache DateUtils parse cost:" + (endtime - starttime) + "ms");
}
}
这里分别用100W个string数组 与100W个Date数组做了实验，结果如下
JDK SimpleDateFormat format cost:1313ms Opencfg DateFormatUtils format cost:844ms Apache FastDateFormat format cost:1860ms
JDK SimpleDateFormat parse cost:3563ms Opencfg DateFormatUtils parse cost:3641ms Apache DateUtils parse cost:16656ms
在单线程测试中，Opencfg DateFormatUtils的format能力 明显高于JDK 40%、Aapache 50%， parse的能力与单线成下的SimpleDateFormat相当， 与Apache的DateUtils明显不在一个级别，性能高出500%。
下边我使用多线程测试：
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.opencfg.core;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import org.apache.commons.lang.time.FastDateFormat;
import org.junit.Before;
import org.junit.Test;
/**
* DateFormatUtils JUnit4 Test
*
* @author Opencfg Software Foundation
* @since 0.0.1-SNAPSHOT
* @version $Id: DateFormatUtilsMutiThreadTest.java 2011-07-18 23:06:53 reymondtu $
*/
public class DateFormatUtilsMutiThreadTest {
private final int TEST_SIZE = 1000000;
private final int TEST_THREAD_COUNT = 10;
private Date[] dateArray = new Date[TEST_SIZE];
private String[] stringArray = new String[TEST_SIZE];
@Before
public void setUp() {
for(int i = 0; i < TEST_SIZE; i++) {
dateArray[i] = new Date();
}
for(int i = 0; i < TEST_SIZE; i++) {
stringArray[i] = DateFormatUtils.safeFormatDate("yyyy-MM-dd HH:mm:ss", new Date());
}
}
/* Format */
@Test
public void test_Apache_FastDateFormat_format() throws InterruptedException {
final FastDateFormat fastDateFormat = FastDateFormat.getInstance();
long starttime = System.currentTimeMillis();
int avr = TEST_SIZE/TEST_THREAD_COUNT;
for(int i = 0; i < TEST_THREAD_COUNT; i ++) {
final int start = i * avr;
final int end = (i + 1) * avr;
Thread t = new Thread(new Runnable() {
@Override
public void run() {
for(int j = start; j < end ; j ++) {
fastDateFormat.format(dateArray[j]);
}
}
});
t.start();
t.join();
}
long endtime = System.currentTimeMillis();
System.out.println("Apache Muti-Thread FastDateFormat format cost:" + (endtime - starttime) + "ms");
}
@Test
public void test_JDK_SimpleDateFormat_format() throws InterruptedException {
long starttime = System.currentTimeMillis();
final SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
int avr = TEST_SIZE/TEST_THREAD_COUNT;
for(int i = 0; i < TEST_THREAD_COUNT; i ++) {
final int start = i * avr;
final int end = (i + 1) * avr;
Thread t = new Thread(new Runnable() {
@Override
public void run() {
for(int j = start; j < end ; j ++) {
sdf.format(dateArray[j]);
}
}
});
t.start();
t.join();
}
long endtime = System.currentTimeMillis();
System.out.println("JDK Muti-Thread SimpleDateFormat format cost:" + (endtime - starttime) + "ms");
}
@Test
public void test_Opencfg_DateFormatUtils_format() throws InterruptedException {
long starttime = System.currentTimeMillis();
int avr = TEST_SIZE/TEST_THREAD_COUNT;
for(int i = 0; i < TEST_THREAD_COUNT; i ++) {
final int start = i * avr;
final int end = (i + 1) * avr;
Thread t = new Thread(new Runnable() {
@Override
public void run() {
for(int j = start; j < end ; j ++) {
DateFormatUtils.safeFormatDate("yyyy-MM-dd HH:mm:ss", dateArray[j]);
}
}
});
t.start();
t.join();
}
long endtime = System.currentTimeMillis();
System.out.println("Opencfg Muti-Thread DateFormatUtils format cost:" + (endtime - starttime) + "ms");
}
/* Parse */
@Test
public void test_Apache_DateUtils_parse() throws ParseException, InterruptedException {
long starttime = System.currentTimeMillis();
final String[] dateParten = new String[]{"yyyy-MM-dd HH:mm:ss"};
int avr = TEST_SIZE/TEST_THREAD_COUNT;
for(int i = 0; i < TEST_THREAD_COUNT; i ++) {
final int start = i * avr;
final int end = (i + 1) * avr;
Thread t = new Thread(new Runnable() {
@Override
public void run() {
for(int j = start; j < end ; j ++) {
try {
org.apache.commons.lang.time.DateUtils.parseDate(stringArray[j], dateParten);
} catch (ParseException e) {
e.printStackTrace();
}
}
}
});
t.start();
t.join();
}
long endtime = System.currentTimeMillis();
System.out.println("Apache Muti-Thread DateUtils parse cost:" + (endtime - starttime) + "ms");
}
@Test
public void test_JDK_SimpleDateFormat_parse() throws ParseException, InterruptedException {
long starttime = System.currentTimeMillis();
final SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
int avr = TEST_SIZE/TEST_THREAD_COUNT;
for(int i = 0; i < TEST_THREAD_COUNT; i ++) {
final int start = i * avr;
final int end = (i + 1) * avr;
Thread t = new Thread(new Runnable() {
@Override
public void run() {
for(int j = start; j < end ; j ++) {
try {
sdf.parse(stringArray[j]);
} catch (ParseException e) {
e.printStackTrace();
}
}
}
});
t.start();
t.join();
}
long endtime = System.currentTimeMillis();
System.out.println("JDK Muti-Thread SimpleDateFormat parse cost:" + (endtime - starttime) + "ms");
}
@Test
public void test_Opencfg_DateFormatUtils_parse() throws ParseException, InterruptedException {
long starttime = System.currentTimeMillis();
int avr = TEST_SIZE/TEST_THREAD_COUNT;
for(int i = 0; i < TEST_THREAD_COUNT; i ++) {
final int start = i * avr;
final int end = (i + 1) * avr;
Thread t = new Thread(new Runnable() {
@Override
public void run() {
for(int j = start; j < end ; j ++) {
try {
DateFormatUtils.safeParseDate("yyyy-MM-dd HH:mm:ss", stringArray[j]);
} catch (ParseException e) {
e.printStackTrace();
}
}
}
});
t.start();
t.join();
}
long endtime = System.currentTimeMillis();
System.out.println("Opencfg Muti-Thread DateFormatUtils parse cost:" + (endtime - starttime) + "ms");
}
}
这里还是使用了100W个String，100W个Date， 每个测试开启10个线程， 测试结果如下：
Apache Muti-Thread FastDateFormat format cost:2265ms JDK Muti-Thread SimpleDateFormat format cost:766ms Opencfg Muti-Thread DateFormatUtils format cost:891ms
Apache Muti-Thread DateUtils parse cost:16766ms JDK Muti-Thread SimpleDateFormat parse cost:3594ms Opencfg Muti-Thread DateFormatUtils parse cost:3860ms
从结果中可以看出Opencfg的DateFormatUtils性能接近与SimpleDateFormat，远远高出Apache的FastDateFormat与DateUtils，同时又提供了基于ThreadLocal的线程安全保障。：）
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评论
2 楼
tuhaitao
2011-09-06
heritrix 写道
private static DateFormat getFormat(final String dateParten){
return (DateFormat)threadLocal.get().get(dateParten);
}
这里threadLocal取出来， 怎么不用close?
return (DateFormat)threadLocal.get().get(dateParten);
}
这里threadLocal取出来， 怎么不用close?
你说的是ThreadLocal的remove()吧，貌似木有close()方法，
这里肯定不能remove，因为要缓存，如果remove了，每次都要new SimpleDateFormat,性能很低
1 楼
heritrix
2011-07-19
private static DateFormat getFormat(final String dateParten){
return (DateFormat)threadLocal.get().get(dateParten);
}
这里threadLocal取出来， 怎么不用close?
return (DateFormat)threadLocal.get().get(dateParten);
}
这里threadLocal取出来， 怎么不用close?
发表评论
-
import static简化代码
2011-11-03 00:10 1631喜欢定义常量的哥们你伤不起啊，好处当然是大大滴，但是定义的名字 ... -
Java永远的伤-中国1927年12月31日午夜
2011-08-15 20:44 3838话说在中国1927年12月31日午 ... -
xss漏洞之进制转换
2011-07-18 01:17 11160SQL注入的事件已经是上个世纪最令人头疼的攻击方法，21世纪又 ... -
tomcat关不掉的原因
2011-07-12 23:51 43407tomcat/bin 目录下的catalina.sh是比较常用 ... -
接口调用频率限制代码
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2011-05-18 02:04 10646简单的不带通配符linux命令调用非常简单，使用Runtime ... -
Java位运算的优势
2011-04-09 01:58 2237在Java中对数据的运算，有很好的规范支持，尤其是针对二进制的 ... -
Facebook BigPipe技术
2011-01-04 00:37 2652关于web应用，从html的产生，到客户端浏览器的渲染， ... -
SimpleDateFormat性能调优
2010-11-25 00:12 4145万能的SimpleDateFormat可以把java.util ... -
JMX学习笔记(三)-MXBean
2010-11-10 11:25 4943在MBean中有只要遵循以下两个规则，我们就可以在jc ... -
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2010-11-07 15:25 8936Notification 通知，也可理解为消息，有通知，必 ... -
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2010-10-16 16:27 13598JMX 即 Java Management Ex ... -
cookie安全
2010-07-06 01:09 4112cookie的domian,path，expires, ... -
native2ascii转换后仍然乱码
2010-04-18 17:47 1769native2ascii转换的时候如果不带-encoding ... -
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2010-01-26 11:36 2584今天跟一个同事调试代码，突然发现，诸如findUser ... -
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java中获得当前目录的各种方法
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