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Summary: Nested | Field | Method | Constr | Detail: Nested | Field | Method | Constr |
java.lang.Object
java.awt.PageAttributes
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Constructor Summary | |
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Method Summary | |
Object |
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boolean | |
PageAttributes.ColorType |
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PageAttributes.MediaType |
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PageAttributes.OrientationRequestedType | |
PageAttributes.OriginType | |
PageAttributes.PrintQualityType | |
int[] | |
int |
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void |
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void |
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void |
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void |
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void |
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String |
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Methods inherited from class java.lang.Object | |
clone , equals , extends Object> getClass , finalize , hashCode , notify , notifyAll , toString , wait , wait , wait |
public PageAttributes()
The basic constructor. Object is special, because it has no superclass, so there is no call to super().
public PageAttributes(PageAttributes.ColorType color, PageAttributes.MediaType media, PageAttributes.OrientationRequestedType orientation, PageAttributes.OriginType origin, PageAttributes.PrintQualityType quality, int[] resolution)
public Object clone()
This method may be called to create a new copy of the Object. The typical behavior is as follows:
o == o.clone()
is falseo.getClass() == o.clone().getClass()
is trueo.equals(o)
is trueHowever, these are not strict requirements, and may be violated if necessary. Of the three requirements, the last is the most commonly violated, particularly if the subclass does not override
Object.equals(Object)
.If the Object you call clone() on does not implement
Cloneable
(which is a placeholder interface), then a CloneNotSupportedException is thrown. Notice that Object does not implement Cloneable; this method exists as a convenience for subclasses that do.Object's implementation of clone allocates space for the new Object using the correct class, without calling any constructors, and then fills in all of the new field values with the old field values. Thus, it is a shallow copy. However, subclasses are permitted to make a deep copy.
All array types implement Cloneable, and override this method as follows (it should never fail):
public Object clone() { try { super.clone(); } catch (CloneNotSupportedException e) { throw new InternalError(e.getMessage()); } }
- Returns:
- a copy of the Object
- See Also:
Cloneable
public boolean equals(Object o)
Determine whether this Object is semantically equal to another Object.There are some fairly strict requirements on this method which subclasses must follow:
- It must be transitive. If
a.equals(b)
andb.equals(c)
, thena.equals(c)
must be true as well.- It must be symmetric.
a.equals(b)
andb.equals(a)
must have the same value.- It must be reflexive.
a.equals(a)
must always be true.- It must be consistent. Whichever value a.equals(b) returns on the first invocation must be the value returned on all later invocations.
a.equals(null)
must be false.- It must be consistent with hashCode(). That is,
a.equals(b)
must implya.hashCode() == b.hashCode()
. The reverse is not true; two objects that are not equal may have the same hashcode, but that has the potential to harm hashing performance.This is typically overridden to throw a
ClassCastException
if the argument is not comparable to the class performing the comparison, but that is not a requirement. It is legal fora.equals(b)
to be true even thougha.getClass() != b.getClass()
. Also, it is typical to never cause aNullPointerException
.In general, the Collections API (
java.util
) use theequals
method rather than the==
operator to compare objects. However,IdentityHashMap
is an exception to this rule, for its own good reasons.The default implementation returns
this == o
.
- Parameters:
- Returns:
- whether this Object is semantically equal to another
- See Also:
Object.hashCode()
public int hashCode()
Get a value that represents this Object, as uniquely as possible within the confines of an int.There are some requirements on this method which subclasses must follow:
- Semantic equality implies identical hashcodes. In other words, if
a.equals(b)
is true, thena.hashCode() == b.hashCode()
must be as well. However, the reverse is not necessarily true, and two objects may have the same hashcode without being equal.- It must be consistent. Whichever value o.hashCode() returns on the first invocation must be the value returned on all later invocations as long as the object exists. Notice, however, that the result of hashCode may change between separate executions of a Virtual Machine, because it is not invoked on the same object.
Notice that since
hashCode
is used inHashtable
and other hashing classes, a poor implementation will degrade the performance of hashing (so don't blindly implement it as returning a constant!). Also, if calculating the hash is time-consuming, a class may consider caching the results.The default implementation returns
System.identityHashCode(this)
- Returns:
- the hash code for this Object
public void setOrientationRequested(PageAttributes.OrientationRequestedType orientation)
public String toString()
Convert this Object to a human-readable String. There are no limits placed on how long this String should be or what it should contain. We suggest you make it as intuitive as possible to be able to place it intoSystem.out.println()
and such.It is typical, but not required, to ensure that this method never completes abruptly with a
RuntimeException
.This method will be called when performing string concatenation with this object. If the result is
null
, string concatenation will instead use"null"
.The default implementation returns
getClass().getName() + "@" + Integer.toHexString(hashCode())
.
- Returns:
- the String representing this Object, which may be null
- See Also:
getClass()
,Object.hashCode()
,Class.getName()
,Integer.toHexString(int)