I was referring to a functional test, not a performance test.
On 8/27/08, Sean Qiu <[EMAIL PROTECTED]> wrote:
> Here is a small test from Regis:
>
> ----------
> int count = 5000;
>
> for (int i = 0; i < count; ++i) { new Date(new
> java.util.Date().getTime()).toString(); }
>
> Date date = new Date(new java.util.Date().getTime());
> long start = System.currentTimeMillis();
>
> for (int i = 0; i < count; ++i) { date.toString(); }
> long end = System.currentTimeMillis();
> System.out.println("Invoke Date.toString() " + count + " times, cost:
> " + (end - start));
>
> Time time = new Time(new java.util.Date().getTime());
> start = System.currentTimeMillis();
> for (int i = 0; i < count; ++i) { time.toString(); }
> end = System.currentTimeMillis();
> System.out.println("Invoke Time.toString() " + count + " times, cost:
> " + (end - start));
>
> Timestamp timestamp = new Timestamp(new java.util.Date().getTime());
> start = System.currentTimeMillis();
> for (int i = 0; i < count; ++i) { timestamp.toString(); }
> end = System.currentTimeMillis();
> System.out.println("Invoke Timestamp.toString() " + count + " times,
> cost: " + (end - start));
> -------------
>
> the first loop, give time for jvm to warm up
>
> Below data compare the two implementations:
>
> before the patch:
> Invoke Date.toString() 5000 times, cost: 6757
> Invoke Time.toString() 5000 times, cost: 7699
> Invoke Timestamp.toString() 5000 times, cost: 2527
>
> after the patch:
> Invoke Date.toString() 5000 times, cost: 84
> Invoke Time.toString() 5000 times, cost: 95
> Invoke Timestamp.toString() 5000 times, cost: 272
>
>
> We can gain obvious improvement.
>
> 2008/8/28 Nathan Beyer <[EMAIL PROTECTED]>:
>> Are there any associated test cases with this change? On a quick
>> cursory look, I didn't see any existing tests. Did I miss them? If
>> not, we need to start requiring some test cases for "simple
>> improvements" like this to continue functional correctness.
>>
>> -Nathan
>>
>> On Tue, Aug 26, 2008 at 3:59 AM, <[EMAIL PROTECTED]> wrote:
>>> Author: qiuxx
>>> Date: Tue Aug 26 01:59:50 2008
>>> New Revision: 689001
>>>
>>> URL: http://svn.apache.org/viewvc?rev=689001&view=rev
>>> Log:
>>> Apply for HARMONY-5958,([classlib][sql][performance] - improve
>>> performance of java.sql.Date/Time/Timestamp.toString())
>>>
>>> Modified:
>>>
>>> harmony/enhanced/classlib/trunk/modules/sql/src/main/java/java/sql/Date.java
>>>
>>> harmony/enhanced/classlib/trunk/modules/sql/src/main/java/java/sql/Time.java
>>>
>>> harmony/enhanced/classlib/trunk/modules/sql/src/main/java/java/sql/Timestamp.java
>>>
>>> Modified:
>>> harmony/enhanced/classlib/trunk/modules/sql/src/main/java/java/sql/Date.java
>>> URL:
>>> http://svn.apache.org/viewvc/harmony/enhanced/classlib/trunk/modules/sql/src/main/java/java/sql/Date.java?rev=689001&r1=689000&r2=689001&view=diff
>>> ==============================================================================
>>> ---
>>> harmony/enhanced/classlib/trunk/modules/sql/src/main/java/java/sql/Date.java
>>> (original)
>>> +++
>>> harmony/enhanced/classlib/trunk/modules/sql/src/main/java/java/sql/Date.java
>>> Tue Aug 26 01:59:50 2008
>>> @@ -17,8 +17,6 @@
>>>
>>> package java.sql;
>>>
>>> -import java.text.SimpleDateFormat;
>>> -
>>> /**
>>> * A Date class which can consume and produce dates in SQL Date format.
>>> * <p>
>>> @@ -175,8 +173,28 @@
>>> */
>>> @Override
>>> public String toString() {
>>> - SimpleDateFormat dateFormat = new
>>> SimpleDateFormat("yyyy-MM-dd"); //$NON-NLS-1$
>>> - return dateFormat.format(this);
>>> + StringBuilder sb = new StringBuilder(10);
>>> +
>>> + format((getYear() + 1900), 4, sb);
>>> + sb.append('-');
>>> + format((getMonth() + 1), 2, sb);
>>> + sb.append('-');
>>> + format(getDate(), 2, sb);
>>> +
>>> + return sb.toString();
>>> + }
>>> +
>>> + private static final String PADDING = "0000"; //$NON-NLS-1$
>>> +
>>> + /*
>>> + * Private method to format the time
>>> + */
>>> + private void format(int date, int digits, StringBuilder sb) {
>>> + String str = String.valueOf(date);
>>> + if (digits - str.length() > 0) {
>>> + sb.append(PADDING.substring(0, digits - str.length()));
>>> + }
>>> + sb.append(str);
>>> }
>>>
>>> /**
>>>
>>> Modified:
>>> harmony/enhanced/classlib/trunk/modules/sql/src/main/java/java/sql/Time.java
>>> URL:
>>> http://svn.apache.org/viewvc/harmony/enhanced/classlib/trunk/modules/sql/src/main/java/java/sql/Time.java?rev=689001&r1=689000&r2=689001&view=diff
>>> ==============================================================================
>>> ---
>>> harmony/enhanced/classlib/trunk/modules/sql/src/main/java/java/sql/Time.java
>>> (original)
>>> +++
>>> harmony/enhanced/classlib/trunk/modules/sql/src/main/java/java/sql/Time.java
>>> Tue Aug 26 01:59:50 2008
>>> @@ -17,7 +17,6 @@
>>>
>>> package java.sql;
>>>
>>> -import java.text.SimpleDateFormat;
>>> import java.util.Date;
>>>
>>> /**
>>> @@ -180,8 +179,28 @@
>>> */
>>> @Override
>>> public String toString() {
>>> - SimpleDateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
>>> //$NON-NLS-1$
>>> - return dateFormat.format(this);
>>> + StringBuilder sb = new StringBuilder(8);
>>> +
>>> + format(getHours(), 2, sb);
>>> + sb.append(':');
>>> + format(getMinutes(), 2, sb);
>>> + sb.append(':');
>>> + format(getSeconds(), 2, sb);
>>> +
>>> + return sb.toString();
>>> + }
>>> +
>>> + private static final String PADDING = "00"; //$NON-NLS-1$
>>> +
>>> + /*
>>> + * Private method to format the time
>>> + */
>>> + private void format(int date, int digits, StringBuilder sb) {
>>> + String str = String.valueOf(date);
>>> + if (digits - str.length() > 0) {
>>> + sb.append(PADDING.substring(0, digits - str.length()));
>>> + }
>>> + sb.append(str);
>>> }
>>>
>>> /**
>>>
>>> Modified:
>>> harmony/enhanced/classlib/trunk/modules/sql/src/main/java/java/sql/Timestamp.java
>>> URL:
>>> http://svn.apache.org/viewvc/harmony/enhanced/classlib/trunk/modules/sql/src/main/java/java/sql/Timestamp.java?rev=689001&r1=689000&r2=689001&view=diff
>>> ==============================================================================
>>> ---
>>> harmony/enhanced/classlib/trunk/modules/sql/src/main/java/java/sql/Timestamp.java
>>> (original)
>>> +++
>>> harmony/enhanced/classlib/trunk/modules/sql/src/main/java/java/sql/Timestamp.java
>>> Tue Aug 26 01:59:50 2008
>>> @@ -309,62 +309,43 @@
>>> @SuppressWarnings("deprecation")
>>> @Override
>>> public String toString() {
>>> - /*
>>> - * Use a DecimalFormat to lay out the nanosecond value as a
>>> simple
>>> - * string of 9 integers, with leading Zeros
>>> - */
>>> - DecimalFormat decimalFormat = new DecimalFormat("0");
>>> //$NON-NLS-1$
>>> - decimalFormat.setMinimumIntegerDigits(9);
>>> - decimalFormat.setMaximumIntegerDigits(9);
>>> - String theNanos = decimalFormat.format(nanos);
>>> - theNanos = stripTrailingZeros(theNanos);
>>> -
>>> - String year = format((getYear() + 1900), 4);
>>> - String month = format((getMonth() + 1), 2);
>>> - String date = format(getDate(), 2);
>>> - String hours = format(getHours(), 2);
>>> - String minutes = format(getMinutes(), 2);
>>> - String seconds = format(getSeconds(), 2);
>>> -
>>> - return year + '-' + month + '-' + date + ' ' + hours + ':' +
>>> minutes
>>> - + ':' + seconds + '.' + theNanos;
>>> - }
>>> + StringBuilder sb = new StringBuilder(29);
>>>
>>> - /*
>>> - * Private method to format the time
>>> - */
>>> - private String format(int date, int digits) {
>>> - StringBuilder dateStringBuffer = new
>>> StringBuilder(String.valueOf(date));
>>> - while (dateStringBuffer.length() < digits) {
>>> - dateStringBuffer = dateStringBuffer.insert(0, '0');
>>> + format((getYear() + 1900), 4, sb);
>>> + sb.append('-');
>>> + format((getMonth() + 1), 2, sb);
>>> + sb.append('-');
>>> + format(getDate(), 2, sb);
>>> + sb.append(' ');
>>> + format(getHours(), 2, sb);
>>> + sb.append(':');
>>> + format(getMinutes(), 2, sb);
>>> + sb.append(':');
>>> + format(getSeconds(), 2, sb);
>>> + sb.append('.');
>>> + if (nanos == 0) {
>>> + sb.append('0');
>>> + } else {
>>> + format(nanos, 9, sb);
>>> + while (sb.charAt(sb.length() - 1) == '0') {
>>> + sb.setLength(sb.length() - 1);
>>> + }
>>> }
>>> - return dateStringBuffer.toString();
>>> +
>>> + return sb.toString();
>>> }
>>>
>>> - /*
>>> - * Private method to strip trailing '0' characters from a string.
>>> @param
>>> - * inputString the starting string @return a string with the
>>> trailing zeros
>>> - * stripped - will leave a single 0 at the beginning of the string
>>> - */
>>> - private String stripTrailingZeros(String inputString) {
>>> - String finalString;
>>> + private static final String PADDING = "000000000"; //$NON-NLS-1$
>>>
>>> - int i;
>>> - for (i = inputString.length(); i > 0; i--) {
>>> - if (inputString.charAt(i - 1) != '0') {
>>> - break;
>>> - }
>>> - /*
>>> - * If the string has a 0 as its first character, return a
>>> string
>>> - * with a single '0'
>>> - */
>>> - if (i == 1) {
>>> - return "0"; //$NON-NLS-1$
>>> - }
>>> + /*
>>> + * Private method to format the time
>>> + */
>>> + private void format(int date, int digits, StringBuilder sb) {
>>> + String str = String.valueOf(date);
>>> + if (digits - str.length() > 0) {
>>> + sb.append(PADDING.substring(0, digits - str.length()));
>>> }
>>> -
>>> - finalString = inputString.substring(0, i);
>>> - return finalString;
>>> + sb.append(str);
>>> }
>>>
>>> /**
>>>
>>>
>>>
>>
>
>
>
> --
> Best Regards
> Sean, Xiao Xia Qiu
>
> China Software Development Lab, IBM
>
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