问题
I need to add the current date into a prepared statement of a JDBC call. I need to add the date in a format like yyyy/MM/dd
.
I've try with
DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd");
Date date = new Date();
pstm.setDate(6, (java.sql.Date) date);
but I have this error:
threw exception
java.lang.ClassCastException: java.util.Date cannot be cast to java.sql.Date
Is there a way to obtain a java.sql.Date
object with the same format?
回答1:
A java.util.Date
is not a java.sql.Date
. It's the other way around. A java.sql.Date
is a java.util.Date
.
You'll need to convert it to a java.sql.Date
by using the constructor that takes a long that a java.util.Date
can supply.
java.sql.Date sqlDate = new java.sql.Date(utilDate.getTime());
回答2:
Simply in one line:
java.sql.Date date = new java.sql.Date(Calendar.getInstance().getTime().getTime());
回答3:
new java.sql.Date(Calendar.getInstance().getTimeInMillis());
回答4:
These are all too long.
Just use:
new Date(System.currentTimeMillis())
回答5:
tl;dr
myPreparedStatement.setObject( // Directly exchange java.time objects with database without the troublesome old java.sql.* classes.
… ,
LocalDate.parse( // Parse string as a `LocalDate` date-only value.
"2018-01-23" // Input string that complies with standard ISO 8601 formatting.
)
)
java.time
The modern approach uses the java.time classes that supplant the troublesome old legacy classes such as java.util.Date
and java.sql.Date
.
For a date-only value, use LocalDate
. The LocalDate class represents a date-only value without time-of-day and without time zone.
The java.time classes use standard formats when parsing/generating strings. So no need to specify a formatting pattern.
LocalDate ld = LocalDate.parse( input ) ;
You can directly exchange java.time objects with your database using a JDBC driver compliant with JDBC 4.2 or later. You can forget about transforming in and out of java.sql.* classes.
myPreparedStatement.setObject( … , ld ) ;
Retrieval:
LocalDate ld = myResultSet.getObject( … , LocalDate.class ) ;
About java.time
The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.
The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.
To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.
Where to obtain the java.time classes?
- Java SE 8, Java SE 9, and later
- Built-in.
- Part of the standard Java API with a bundled implementation.
- Java 9 adds some minor features and fixes.
- Java SE 6 and Java SE 7
- Much of the java.time functionality is back-ported to Java 6 & 7 in ThreeTen-Backport.
- Android
- Later versions of Android bundle implementations of the java.time classes.
- For earlier Android, the ThreeTenABP project adapts ThreeTen-Backport (mentioned above). See How to use ThreeTenABP….
The ThreeTen-Extra project extends java.time with additional classes. This project is a proving ground for possible future additions to java.time. You may find some useful classes here such as Interval, YearWeek, YearQuarter, and more.
回答6:
Will do:
new Date(Instant.now().toEpochMilli())
回答7:
You can achieve you goal with below ways :-
long millis=System.currentTimeMillis();
java.sql.Date date=new java.sql.Date(millis);
or
// create a java calendar instance
Calendar calendar = Calendar.getInstance();
// get a java date (java.util.Date) from the Calendar instance.
// this java date will represent the current date, or "now".
java.util.Date currentDate = calendar.getTime();
// now, create a java.sql.Date from the java.util.Date
java.sql.Date date = new java.sql.Date(currentDate.getTime());
回答8:
all you have to do is this
Calendar currenttime = Calendar.getInstance(); //creates the Calendar object of the current time
Date sqldate = new Date((currenttime.getTime()).getTime()); //creates the sql Date of the above created object
pstm.setDate(6, (java.sql.Date) date); //assign it to the prepared statement (pstm in this case)
来源:https://stackoverflow.com/questions/18257648/get-the-current-date-in-java-sql-date-format