com.caucho.el
Class NullLiteral

java.lang.Object
  extended by javax.el.Expression
      extended by javax.el.ValueExpression
          extended by com.caucho.el.Expr
              extended by com.caucho.el.NullLiteral
All Implemented Interfaces:
java.io.Serializable

public class NullLiteral
extends Expr

Represents a null literal expression.

See Also:
Serialized Form

Field Summary
 
Fields inherited from class com.caucho.el.Expr
L, log
 
Constructor Summary
NullLiteral()
          Create the literal.
 
Method Summary
 boolean equals(java.lang.Object o)
          Returns true for equal strings.
 java.lang.Object getValue(ELContext env)
          Evaluate the expression as an object.
 boolean isConstant()
          Returns true if the expression is constant.
 boolean print(WriteStream out, ELContext env, boolean isEscaped)
          Evalutes directly to the output.
 void printCreate(WriteStream os)
          Prints the code to create an LongLiteral.
 java.lang.String toString()
          Returns a printable view.
 
Methods inherited from class com.caucho.el.Expr
coerceToType, createField, createField, createMethod, error, evalBigDecimal, evalBigInteger, evalBoolean, evalCharacter, evalDouble, evalLong, evalObject, evalPeriod, evalString, evalStringWithNull, getExpectedType, getExpressionString, getMethodInfo, getType, hashCode, invocationError, invoke, isDouble, isDoubleString, isLiteralText, isReadOnly, print, printEscaped, printEscapedString, setProperty, setValue, toBigDecimal, toBigInteger, toBoolean, toCharacter, toDouble, toEnum, toLong, toStream, toStream, toStream, toStreamEscaped, toStreamEscaped, toStreamEscaped, toString, toString, toString, toString, toString, toStringWithNull
 
Methods inherited from class javax.el.ValueExpression
getValueReference
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Constructor Detail

NullLiteral

public NullLiteral()
Create the literal.

Method Detail

isConstant

public boolean isConstant()
Returns true if the expression is constant.

Overrides:
isConstant in class Expr

getValue

public java.lang.Object getValue(ELContext env)
                          throws ELException
Evaluate the expression as an object.

Specified by:
getValue in class Expr
Parameters:
env - the variable environment
Returns:
null
Throws:
ELException

print

public boolean print(WriteStream out,
                     ELContext env,
                     boolean isEscaped)
              throws java.io.IOException,
                     ELException
Evalutes directly to the output.

Overrides:
print in class Expr
Parameters:
out - the output writer
env - the variable environment
isEscaped - if true, escape reserved XML
Returns:
true if the object is null, otherwise false
Throws:
java.io.IOException
ELException

printCreate

public void printCreate(WriteStream os)
                 throws java.io.IOException
Prints the code to create an LongLiteral.

Overrides:
printCreate in class Expr
Parameters:
os - the stream to the *.java page
Throws:
java.io.IOException

equals

public boolean equals(java.lang.Object o)
Returns true for equal strings.

Overrides:
equals in class Expr

toString

public java.lang.String toString()
Returns a printable view.

Specified by:
toString in class Expr