Java compact2, compact3 java.sql Class Timestamp（JDK8）

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Java™ Platform
Standard Ed. 8

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Method

Detail:
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Constr |
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java.lang.Object
- java.util.Date
- - java.sql.Timestamp

All Implemented Interfaces:

Serializable, Cloneable, Comparable<Date>
```
public class Timestamp
extends Date
```
A thin wrapper around java.util.Date that allows the JDBC API to identify this as an SQL TIMESTAMP value. It adds the ability to hold the SQL TIMESTAMP fractional seconds value, by allowing the specification of fractional seconds to a precision of nanoseconds. A Timestamp also provides formatting and parsing operations to support the JDBC escape syntax for timestamp values.

The precision of a Timestamp object is calculated to be either:
- 19 , which is the number of characters in yyyy-mm-dd hh:mm:ss
- 20 + s , which is the number of characters in the yyyy-mm-dd hh:mm:ss.[fff...] and s represents the scale of the given Timestamp, its fractional seconds precision.
Note: This type is a composite of a java.util.Date and a separate nanoseconds value. Only integral seconds are stored in the java.util.Date component. The fractional seconds - the nanos - are separate. The Timestamp.equals(Object) method never returns true when passed an object that isn't an instance of java.sql.Timestamp, because the nanos component of a date is unknown. As a result, the Timestamp.equals(Object) method is not symmetric with respect to the java.util.Date.equals(Object) method. Also, the hashCode method uses the underlying java.util.Date implementation and therefore does not include nanos in its computation.

Due to the differences between the Timestamp class and the java.util.Date class mentioned above, it is recommended that code not view Timestamp values generically as an instance of java.util.Date. The inheritance relationship between Timestamp and java.util.Date really denotes implementation inheritance, and not type inheritance.
See Also:

Serialized Form

Constructor Summary

Constructors
Constructor and Description
`Timestamp(int year, int month, int date, int hour, int minute, int second, int nano)` Deprecated. instead use the constructor `Timestamp(long millis)`
`Timestamp(long time)` Constructs a `Timestamp` object using a milliseconds time value.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`after(Timestamp ts)` Indicates whether this `Timestamp` object is later than the given `Timestamp` object.
`boolean`	`before(Timestamp ts)` Indicates whether this `Timestamp` object is earlier than the given `Timestamp` object.
`int`	`compareTo(Date o)` Compares this `Timestamp` object to the given `Date` object.
`int`	`compareTo(Timestamp ts)` Compares this `Timestamp` object to the given `Timestamp` object.
`boolean`	`equals(Object ts)` Tests to see if this `Timestamp` object is equal to the given object.
`boolean`	`equals(Timestamp ts)` Tests to see if this `Timestamp` object is equal to the given `Timestamp` object.
`static Timestamp`	`from(Instant instant)` Obtains an instance of `Timestamp` from an `Instant` object.
`int`	`getNanos()` Gets this `Timestamp` object's `nanos` value.
`long`	`getTime()` Returns the number of milliseconds since January 1, 1970, 00:00:00 GMT represented by this `Timestamp` object.
`int`	`hashCode()` Returns a hash code value for this object.
`void`	`setNanos(int n)` Sets this `Timestamp` object's `nanos` field to the given value.
`void`	`setTime(long time)` Sets this `Timestamp` object to represent a point in time that is `time` milliseconds after January 1, 1970 00:00:00 GMT.
`Instant`	`toInstant()` Converts this `Timestamp` object to an `Instant`.
`LocalDateTime`	`toLocalDateTime()` Converts this `Timestamp` object to a `LocalDateTime`.
`String`	`toString()` Formats a timestamp in JDBC timestamp escape format.
`static Timestamp`	`valueOf(LocalDateTime dateTime)` Obtains an instance of `Timestamp` from a `LocalDateTime` object, with the same year, month, day of month, hours, minutes, seconds and nanos date-time value as the provided `LocalDateTime`.
`static Timestamp`	`valueOf(String s)` Converts a `String` object in JDBC timestamp escape format to a `Timestamp` value.

Methods inherited from class java.util.Date
after, before, clone, getDate, getDay, getHours, getMinutes, getMonth, getSeconds, getTimezoneOffset, getYear, parse, setDate, setHours, setMinutes, setMonth, setSeconds, setYear, toGMTString, toLocaleString, UTC

Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - Timestamp
```
@Deprecated
public Timestamp(int year,
                             int month,
                             int date,
                             int hour,
                             int minute,
                             int second,
                             int nano)
```
    Deprecated. instead use the constructor Timestamp(long millis)
    
    Constructs a Timestamp object initialized with the given values.
    
    Parameters:
    
    year - the year minus 1900
    
    month - 0 to 11
    
    date - 1 to 31
    
    hour - 0 to 23
    
    minute - 0 to 59
    
    second - 0 to 59
    
    nano - 0 to 999,999,999
    
    Throws:
    
    IllegalArgumentException - if the nano argument is out of bounds
  - Timestamp
```
public Timestamp(long time)
```
    Constructs a Timestamp object using a milliseconds time value. The integral seconds are stored in the underlying date value; the fractional seconds are stored in the nanos field of the Timestamp object.
    
    Parameters:
    
    time - milliseconds since January 1, 1970, 00:00:00 GMT. A negative number is the number of milliseconds before January 1, 1970, 00:00:00 GMT.
    
    See Also:
    
    Calendar
- Method Detail
  - setTime
```
public void setTime(long time)
```
    Sets this Timestamp object to represent a point in time that is time milliseconds after January 1, 1970 00:00:00 GMT.
    
    Overrides:
    
    setTime in class Date
    
    Parameters:
    
    time - the number of milliseconds.
    
    See Also:
    
    getTime(), Timestamp(long time), Calendar
  - getTime
```
public long getTime()
```
    Returns the number of milliseconds since January 1, 1970, 00:00:00 GMT represented by this Timestamp object.
    
    Overrides:
    
    getTime in class Date
    
    Returns:
    
    the number of milliseconds since January 1, 1970, 00:00:00 GMT represented by this date.
    
    See Also:
    
    setTime(long)
  - valueOf
```
public static Timestamp valueOf(String s)
```
    Converts a String object in JDBC timestamp escape format to a Timestamp value.
    
    Parameters:
    
    s - timestamp in format yyyy-[m]m-[d]d hh:mm:ss[.f...]. The fractional seconds may be omitted. The leading zero for mm and dd may also be omitted.
    
    Returns:
    
    corresponding Timestamp value
    
    Throws:
    
    IllegalArgumentException - if the given argument does not have the format yyyy-[m]m-[d]d hh:mm:ss[.f...]
  - toString
```
public String toString()
```
    Formats a timestamp in JDBC timestamp escape format. yyyy-mm-dd hh:mm:ss.fffffffff, where ffffffffff indicates nanoseconds.
    
    Overrides:
    
    toString in class Date
    
    Returns:
    
    a String object in yyyy-mm-dd hh:mm:ss.fffffffff format
    
    See Also:
    
    Date.toLocaleString(), Date.toGMTString()
  - getNanos
```
public int getNanos()
```
    Gets this Timestamp object's nanos value.
    
    Returns:
    
    this Timestamp object's fractional seconds component
    
    See Also:
    
    setNanos(int)
  - setNanos
```
public void setNanos(int n)
```
    Sets this Timestamp object's nanos field to the given value.
    
    Parameters:
    
    n - the new fractional seconds component
    
    Throws:
    
    IllegalArgumentException - if the given argument is greater than 999999999 or less than 0
    
    See Also:
    
    getNanos()
  - equals
```
public boolean equals(Timestamp ts)
```
    Tests to see if this Timestamp object is equal to the given Timestamp object.
    
    Parameters:
    
    ts - the Timestamp value to compare with
    
    Returns:
    
    true if the given Timestamp object is equal to this Timestamp object; false otherwise
  - equals
```
public boolean equals(Object ts)
```
    Tests to see if this Timestamp object is equal to the given object. This version of the method equals has been added to fix the incorrect signature of Timestamp.equals(Timestamp) and to preserve backward compatibility with existing class files. Note: This method is not symmetric with respect to the equals(Object) method in the base class.
    
    Overrides:
    
    equals in class Date
    
    Parameters:
    
    ts - the Object value to compare with
    
    Returns:
    
    true if the given Object is an instance of a Timestamp that is equal to this Timestamp object; false otherwise
    
    See Also:
    
    Date.getTime()
  - before
```
public boolean before(Timestamp ts)
```
    Indicates whether this Timestamp object is earlier than the given Timestamp object.
    
    Parameters:
    
    ts - the Timestamp value to compare with
    
    Returns:
    
    true if this Timestamp object is earlier; false otherwise
  - after
```
public boolean after(Timestamp ts)
```
    Indicates whether this Timestamp object is later than the given Timestamp object.
    
    Parameters:
    
    ts - the Timestamp value to compare with
    
    Returns:
    
    true if this Timestamp object is later; false otherwise
  - compareTo
```
public int compareTo(Timestamp ts)
```
    Compares this Timestamp object to the given Timestamp object.
    
    Parameters:
    
    ts - the Timestamp object to be compared to this Timestamp object
    
    Returns:
    
    the value 0 if the two Timestamp objects are equal; a value less than 0 if this Timestamp object is before the given argument; and a value greater than 0 if this Timestamp object is after the given argument.
    
    Since:
    
    1.4
  - compareTo
```
public int compareTo(Date o)
```
    Compares this Timestamp object to the given Date object.
    
    Specified by:
    
    compareTo in interface Comparable<Date>
    
    Overrides:
    
    compareTo in class Date
    
    Parameters:
    
    o - the Date to be compared to this Timestamp object
    
    Returns:
    
    the value 0 if this Timestamp object and the given object are equal; a value less than 0 if this Timestamp object is before the given argument; and a value greater than 0 if this Timestamp object is after the given argument.
    
    Since:
    
    1.5
  - hashCode
```
public int hashCode()
```
    Returns a hash code value for this object. The result is the exclusive OR of the two halves of the primitive long value returned by the Date.getTime() method. That is, the hash code is the value of the expression:
    (int)(this.getTime()^(this.getTime() >>> 32))
    The hashCode method uses the underlying java.util.Date implementation and therefore does not include nanos in its computation.
    Overrides:
    
    hashCode in class Date
    
    Returns:
    
    a hash code value for this object.
    
    See Also:
    
    Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)
  - valueOf
```
public static Timestamp valueOf(LocalDateTime dateTime)
```
    Obtains an instance of Timestamp from a LocalDateTime object, with the same year, month, day of month, hours, minutes, seconds and nanos date-time value as the provided LocalDateTime.
    The provided LocalDateTime is interpreted as the local date-time in the local time zone.
    
    Parameters:
    
    dateTime - a LocalDateTime to convert
    
    Returns:
    
    a Timestamp object
    
    Throws:
    
    NullPointerException - if dateTime is null.
    
    Since:
    
    1.8
  - toLocalDateTime
```
public LocalDateTime toLocalDateTime()
```
    Converts this Timestamp object to a LocalDateTime.
    The conversion creates a LocalDateTime that represents the same year, month, day of month, hours, minutes, seconds and nanos date-time value as this Timestamp in the local time zone.
    
    Returns:
    
    a LocalDateTime object representing the same date-time value
    
    Since:
    
    1.8
  - from
```
public static Timestamp from(Instant instant)
```
    Obtains an instance of Timestamp from an Instant object.
    Instant can store points on the time-line further in the future and further in the past than Date. In this scenario, this method will throw an exception.
    
    Parameters:
    
    instant - the instant to convert
    
    Returns:
    
    an Timestamp representing the same point on the time-line as the provided instant
    
    Throws:
    
    NullPointerException - if instant is null.
    
    IllegalArgumentException - if the instant is too large to represent as a Timesamp
    
    Since:
    
    1.8
  - toInstant
```
public Instant toInstant()
```
    Converts this Timestamp object to an Instant.
    The conversion creates an Instant that represents the same point on the time-line as this Timestamp.
    
    Overrides:
    
    toInstant in class Date
    
    Returns:
    
    an instant representing the same point on the time-line
    
    Since:
    
    1.8

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Java™ Platform
Standard Ed. 8

All Classes

Summary:
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Field |
Constr |
Method

Detail:
Field |
Constr |
Method

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Java compact2, compact3 java.sql Class Timestamp（JDK8）

Class Timestamp

Constructor Summary

Method Summary

Methods inherited from class java.util.Date

Methods inherited from class java.lang.Object

Constructor Detail

Timestamp

Timestamp

Method Detail

setTime

getTime

valueOf

toString

getNanos

setNanos

equals

equals

before

after

compareTo

compareTo

hashCode

valueOf

toLocalDateTime

from

toInstant