|
|||||||||
| Home >> All >> org >> sablecc >> [ sablecc overview ] | PREV CLASS NEXT CLASS | ||||||||
SUMMARY: JAVADOC | SOURCE | DOWNLOAD | NESTED | FIELD | CONSTR | METHOD |
DETAIL: FIELD | CONSTR | METHOD | ||||||||
org.sablecc.sablecc
Class LR1Item

java.lang.Objectorg.sablecc.sablecc.LR1Item
- All Implemented Interfaces:
- java.lang.Cloneable, java.lang.Comparable
- final class LR1Item
- extends java.lang.Object
- implements java.lang.Cloneable, java.lang.Comparable
- extends java.lang.Object
| Field Summary | |
(package private) LR0Item |
lr0Item
|
(package private) int |
terminal
|
| Constructor Summary | |
(package private) |
LR1Item(LR0Item lr0Item,
int terminal)
|
| Method Summary | |
java.lang.Object |
clone()
This method may be called to create a new copy of the Object. |
int |
compareTo(java.lang.Object object)
Compares this object with another, and returns a numerical result based on the comparison. |
boolean |
equals(java.lang.Object obj)
Determine whether this Object is semantically equal to another Object. |
int |
hashCode()
Get a value that represents this Object, as uniquely as possible within the confines of an int. |
java.lang.String |
toString()
Convert this Object to a human-readable String. |
java.lang.String |
toString(Symbol lookahead)
|
| Methods inherited from class java.lang.Object |
finalize, getClass, notify, notifyAll, wait, wait, wait |
| Field Detail |
lr0Item
final LR0Item lr0Item
terminal
final int terminal
| Constructor Detail |
LR1Item
LR1Item(LR0Item lr0Item, int terminal)
| Method Detail |
clone
public java.lang.Object clone()
- Description copied from class:
java.lang.Object - 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 true
However, 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)>
Object.equals(Object)55 .If the Object you call clone() on does not implement java.lang.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()); } }
equals
public boolean equals(java.lang.Object obj)
- Description copied from class:
java.lang.Object - 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 java.lang.ClassCastException if the argument is not comparable to the class performing the comparison, but that is not a requirement. It is legal for
a.equals(b)to be true even thougha.getClass() != b.getClass(). Also, it is typical to never cause a java.lang.NullPointerException.In general, the Collections API (
java.util) use theequalsmethod rather than the==operator to compare objects. However, java.util.IdentityHashMap is an exception to this rule, for its own good reasons.The default implementation returns
this == o. - It must be transitive. If
hashCode
public int hashCode()
- Description copied from class:
java.lang.Object - 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
hashCodeis used in java.util.Hashtable 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) - Semantic equality implies identical hashcodes. In other
words, if
toString
public java.lang.String toString()
- Description copied from class:
java.lang.Object - 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 into System.out.println() 55
and such.
It is typical, but not required, to ensure that this method never completes abruptly with a java.lang.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()).
toString
public java.lang.String toString(Symbol lookahead)
compareTo
public int compareTo(java.lang.Object object)
- Description copied from interface:
java.lang.Comparable - Compares this object with another, and returns a numerical result based
on the comparison. If the result is negative, this object sorts less
than the other; if 0, the two are equal, and if positive, this object
sorts greater than the other. To translate this into boolean, simply
perform
o1.compareTo(o2) <op> 0, where op is one of <, <=, =, !=, >, or >=.You must make sure that the comparison is mutual, ie.
sgn(x.compareTo(y)) == -sgn(y.compareTo(x))(where sgn() is defined as -1, 0, or 1 based on the sign). This includes throwing an exception in either direction if the two are not comparable; hence,compareTo(null)should always throw an Exception.You should also ensure transitivity, in two forms:
x.compareTo(y) > 0 && y.compareTo(z) > 0impliesx.compareTo(z) > 0; andx.compareTo(y) == 0impliesx.compareTo(z) == y.compareTo(z).- Specified by:
compareToin interfacejava.lang.Comparable
|
|||||||||
| Home >> All >> org >> sablecc >> [ sablecc overview ] | PREV CLASS NEXT CLASS | ||||||||
SUMMARY: JAVADOC | SOURCE | DOWNLOAD | NESTED | FIELD | CONSTR | METHOD |
DETAIL: FIELD | CONSTR | METHOD | ||||||||
JAVADOC
org.sablecc.sablecc.LR1Item