simpledb
Class StringField

java.lang.Object
  simpledb.StringField

All Implemented Interfaces:

Field

public class StringField
extends java.lang.Object
implements Field

Instance of Field that stores a single String of a fixed length.

Field Summary

private int	maxSize
private java.lang.String	value

Constructor Summary

StringField(java.lang.String s, int maxSize)
Constructor.

Method Summary

boolean	compare(Predicate.Op op, Field val) Compare the specified field to the value of this Field.
boolean	equals(java.lang.Object field)
Type	getType() Returns the type of this field (see Type.INT_TYPE or Type.STRING_TYPE
java.lang.String	getValue()
int	hashCode() Hash code.
void	serialize(java.io.DataOutputStream dos) Write this string to dos.
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

value

private java.lang.String value

maxSize

private int maxSize

Constructor Detail

StringField

public StringField(java.lang.String s,
                   int maxSize)

Constructor.

Parameters:

s - The value of this field.

maxSize - The maximum size of this string

Method Detail

getValue

public java.lang.String getValue()

toString

public java.lang.String toString()

Specified by:

toString in interface Field

Overrides:

toString in class java.lang.Object

hashCode

public int hashCode()

Description copied from interface: Field

Hash code. Different Field objects representing the same value should probably return the same hashCode.

Specified by:

hashCode in interface Field

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object field)

Specified by:

equals in interface Field

Overrides:

equals in class java.lang.Object

serialize

public void serialize(java.io.DataOutputStream dos)
               throws java.io.IOException

Write this string to dos. Always writes maxSize + 4 bytes to the passed in dos. First four bytes are string length, next bytes are string, with remainder padded with 0 to maxSize.

Specified by:

serialize in interface Field

Parameters:

dos - Where the string is written

Throws:

java.io.IOException

See Also:

DataOutputStream

compare

public boolean compare(Predicate.Op op,
                       Field val)

Compare the specified field to the value of this Field. Return semantics are as specified by Field.compare

Specified by:

compare in interface Field

Parameters:

op - The operator

val - The value to compare this Field to

Returns:

Whether or not the comparison yields true.

Throws:

IllegalCastException - if val is not a StringField

See Also:

Field.compare(simpledb.Predicate.Op, simpledb.Field)

getType

public Type getType()

Description copied from interface: Field

Returns the type of this field (see Type.INT_TYPE or Type.STRING_TYPE

Specified by:

getType in interface Field

Returns:

the Type for this Field