org.apache.nutch.db
Class Page

java.lang.Object
  org.apache.nutch.db.Page

All Implemented Interfaces:

Cloneable, Comparable, Writable, WritableComparable

public class Page

extends Object

implements WritableComparable, Cloneable

A row in the Page Database.

   type   name    description
 ---------------------------------------------------------------
   byte   VERSION  - A byte indicating the version of this entry.
   String URL      - The url of a page.  This is the primary key.
   128bit ID       - The MD5 hash of the contents of the page.
   64bit  DATE     - The date this page should be refetched.
   byte   RETRIES  - The number of times we've failed to fetch this page.
   byte   INTERVAL - Frequency, in days, this page should be refreshed.
   float  SCORE   - Multiplied into the score for hits on this page.
   float  NEXTSCORE   - Multiplied into the score for hits on this page.
 

Author:

Mike Cafarella, Doug Cutting

Nested Class Summary

static class	Page.Comparator Compares pages by MD5, then by URL.
static class	Page.UrlComparator Compares pages by URL only.

Constructor Summary

Page()
Construct a page ready to be read by readFields(DataInput).

Page(String urlString, float score)

Page(String urlString, float score, float nextScore, long nextFetch)

Page(String urlString, float score, long nextFetch)

Page(String urlString, MD5Hash md5)
Construct a new, default page, due to be fetched.

Method Summary

Object	clone()
int	compareTo(Object o) Compare to another Page object
long	computeDomainID() Compute domain ID from URL
boolean	equals(Object o)
byte	getFetchInterval()
MD5Hash	getMD5()
long	getNextFetchTime()
float	getNextScore()
int	getNumOutlinks()
byte	getRetriesSinceFetch()
float	getScore()
UTF8	getURL()
int	hashCode()
static Page	read(DataInput in)
void	readFields(DataInput in) Reads the fields of this object from in.
void	set(Page that) Copy the contents of another instance into this instance.
void	setFetchInterval(byte fetchInterval)
void	setMD5(MD5Hash md5)
void	setNextFetchTime(long nextFetch)
void	setNumOutlinks(int numOutlinks)
void	setRetriesSinceFetch(int retries)
void	setScore(float score)
void	setScore(float score, float nextScore)
void	setURL(String url)
String	toString() Print out the Page
String	toTabbedString() A tab-delimited text version of the Page's data.
void	write(DataOutput out) Write the bytes out to the bytestream

Methods inherited from class java.lang.Object

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

Constructor Detail

Page

public Page()

Construct a page ready to be read by readFields(DataInput).

Page

public Page(String urlString,
            MD5Hash md5)
     throws MalformedURLException

Construct a new, default page, due to be fetched.

Page

public Page(String urlString,
            float score)
     throws MalformedURLException

Page

public Page(String urlString,
            float score,
            long nextFetch)
     throws MalformedURLException

Page

public Page(String urlString,
            float score,
            float nextScore,
            long nextFetch)
     throws MalformedURLException

Method Detail

readFields

public void readFields(DataInput in)
                throws IOException

Description copied from interface: Writable

Reads the fields of this object from in. For efficiency, implementations should attempt to re-use storage in the existing object where possible.

Specified by:

readFields in interface Writable

Throws:

IOException

set

public void set(Page that)

Copy the contents of another instance into this instance.

write

public void write(DataOutput out)
           throws IOException

Write the bytes out to the bytestream

Specified by:

write in interface Writable

Throws:

IOException

compareTo

public int compareTo(Object o)

Compare to another Page object

Specified by:

compareTo in interface Comparable

read

public static Page read(DataInput in)
                 throws IOException

Throws:

IOException

getURL

public UTF8 getURL()

setURL

public void setURL(String url)
            throws MalformedURLException

Throws:

MalformedURLException

getMD5

public MD5Hash getMD5()

setMD5

public void setMD5(MD5Hash md5)

getNextFetchTime

public long getNextFetchTime()

setNextFetchTime

public void setNextFetchTime(long nextFetch)

getRetriesSinceFetch

public byte getRetriesSinceFetch()

setRetriesSinceFetch

public void setRetriesSinceFetch(int retries)

getFetchInterval

public byte getFetchInterval()

setFetchInterval

public void setFetchInterval(byte fetchInterval)

getNumOutlinks

public int getNumOutlinks()

setNumOutlinks

public void setNumOutlinks(int numOutlinks)

getScore

public float getScore()

getNextScore

public float getNextScore()

setScore

public void setScore(float score)

setScore

public void setScore(float score,
                     float nextScore)

computeDomainID

public long computeDomainID()
                     throws MalformedURLException

Compute domain ID from URL

Throws:

MalformedURLException

toString

public String toString()

Print out the Page

toTabbedString

public String toTabbedString()

A tab-delimited text version of the Page's data.

equals

public boolean equals(Object o)

hashCode

public int hashCode()

clone

public Object clone()