DHTDBMapping.java
| Index Score | ||
|---|---|---|
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com.aelitis.azureus.core.dht.db.impl |
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Azureus |
View: Reasons, Metrics, Source Code
These are the metrics that contribute to the Enerjy Score for this file, ranked by impact. So the metrics listed at the top influence the score to a greater extent that the metrics listed at the bottom.
| Metric | Description | |
|---|---|---|
| LINE_COMMENT | Number of line comments |  |
| WHITESPACE | Number of whitespace lines | |
| EXEC_COMMENTS | Comments in executable code | |
| COMPARISONS | Number of comparison operators | |
| BLOCKS | Number of blocks | |
| JAVA0117 | JAVA0117 Missing javadoc: method 'method' | |
| CYCLOMATIC | Cyclomatic complexity | |
| LINES | Number of lines in the source file | |
| JAVA0145 | JAVA0145 Tab character used in source file | |
| LOC | Lines of code | |
| JAVA0266 | JAVA0266 Use of System.out | |
| ELOC | Effective lines of code | |
| OPERATORS | Number of operators | |
| JAVA0166 | JAVA0166 Generic exception caught | |
| JAVA0170 | JAVA0170 Caught exception not derived from java.lang.Exception | |
| PROGRAM_LENGTH | Halstead program length | |
| SIZE | Size of the file in bytes | |
| EXITS | Procedure exits | |
| OPERANDS | Number of operands | |
| LOOPS | Number of loops | |
| JAVA0034 | JAVA0034 Missing braces in if statement | |
| LOGICAL_LINES | Number of statements | |
| JAVA0254 | JAVA0254 Use enhanced for loop construct instead of Iterator | |
| UNIQUE_OPERANDS | Number of unique operands | |
| PROGRAM_VOCAB | Halstead program vocabulary | |
| FUNCTIONS | Number of function declarations | |
| RETURNS | Number of return points from functions | |
| UNIQUE_OPERATORS | Number of unique operators | |
| INTERFACE_COMPLEXITY | Interface complexity | |
| JAVA0144 | JAVA0144 Line exceeds maximum M characters | |
| JAVA0076 | JAVA0076 Use of magic number | |
| JAVA0283 | JAVA0283 Control variable not updated in loop body | |
| PROGRAM_VOLUME | Halstead program volume | |
| JAVA0136 | JAVA0136 N methods defined in class (maximum: M) | |
| JAVA0126 | JAVA0126 Method declares unchecked exception in throws | |
| JAVA0179 | JAVA0179 Local variable hides visible field | |
| JAVA0110 | JAVA0110 Incorrect javadoc: no @return tag | |
| JAVA0100 | JAVA0100 Class contains N non-final fields (maximum: M) | |
| JAVA0108 | JAVA0108 Incorrect javadoc: no @param tag for 'parameter' | |
| DOC_COMMENT | Number of javadoc comment lines | |
| JAVA0130 | JAVA0130 Non-static method does not use instance fields | |
| PARAMS | Number of formal parameter declarations | |
| JAVA0270 | JAVA0270 Use Java 5.0 enhanced for loop construct to iterate over all elements in an array | |
| NEST_DEPTH | Maximum nesting depth | |
/*
* Created on 03-Feb-2005
* Created by Paul Gardner
* Copyright (C) 2004, 2005, 2006 Aelitis, All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* AELITIS, SAS au capital de 46,603.30 euros
* 8 Allee Lenotre, La Grille Royale, 78600 Le Mesnil le Roi, France.
*
*/
package com.aelitis.azureus.core.dht.db.impl;
import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.util.*;
import org.gudy.azureus2.core3.util.Debug;
import org.gudy.azureus2.core3.util.HashWrapper;
import org.gudy.azureus2.core3.util.SystemTime;
// import org.gudy.azureus2.core3.util.SHA1Hasher;
import com.aelitis.azureus.core.dht.*;
import com.aelitis.azureus.core.dht.impl.DHTLog;
import com.aelitis.azureus.core.dht.transport.DHTTransportContact;
import com.aelitis.azureus.core.util.bloom.BloomFilter;
import com.aelitis.azureus.core.util.bloom.BloomFilterFactory;
/**
* @author parg
*
*/
public class
DHTDBMapping
{
private static final boolean TRACE_ADDS = false;
private DHTDBImpl db;
private HashWrapper key;
private DHTStorageKey adapter_key;
// maps are access order, most recently used at tail, so we cycle values
private Map direct_originator_map = new LinkedHashMap(16, 0.75f, true );
private Map indirect_originator_value_map = new LinkedHashMap(16, 0.75f, true );
private int hits;
private int direct_data_size;
private int indirect_data_size;
private int local_size;
private byte diversification_state = DHT.DT_NONE;
private static final int IP_COUNT_BLOOM_SIZE_INCREASE_CHUNK = 50;
// 4 bit filter - counts up to 15
private BloomFilter ip_count_bloom_filter = BloomFilterFactory.createAddRemove4Bit( IP_COUNT_BLOOM_SIZE_INCREASE_CHUNK );
protected
DHTDBMapping(
DHTDBImpl _db,
HashWrapper _key,
boolean _local )
{
db = _db;
key = _key;
try{
if ( db.getAdapter() != null ){
adapter_key = db.getAdapter().keyCreated( key, _local );
if ( adapter_key != null ){
diversification_state = adapter_key.getDiversificationType();
}
}
}catch( Throwable e ){
Debug.printStackTrace(e);
}
}
protected HashWrapper
getKey()
{
return( key );
}
protected void
updateLocalContact(
DHTTransportContact contact )
{
// pull out all the local values, reset the originator and then
// re-add them
List changed = new ArrayList();
Iterator it = direct_originator_map.values().iterator();
while( it.hasNext()){
DHTDBValueImpl value = (DHTDBValueImpl)it.next();
if ( value.isLocal()){
value.setOriginatorAndSender( contact );
changed.add( value );
direct_data_size -= value.getValue().length;
local_size -= value.getValue().length;
it.remove();
informDeleted( value );
}
}
for (int i=0;i<changed.size();i++){
add((DHTDBValueImpl)changed.get(i));
}
}
// All values have
// 1) a key
// 2) a value
// 3) an originator (the contact who originally published it)
// 4) a sender (the contact who sent it, could be diff for caches)
// rethink time :P
// a) for a value where sender + originator are the same we store a single value
// b) where sender + originator differ we store an entry per originator/value pair as the
// send can legitimately forward multiple values but their originator should differ
// c) the code that adds values is responsible for not accepting values that are either
// to "far away" from our ID, or that are cache-forwards from a contact "too far"
// away.
// for a given key
// c) we only allow up to 8 entries per sending IP address (excluding port)
// d) if multiple entries have the same value the value is only returned once
// e) only the originator can delete an entry
// a) prevents a single sender from filling up the mapping with garbage
// b) prevents the same key->value mapping being held multiple times when sent by different caches
// c) prevents multiple senders from same IP filling up, but supports multiple machines behind NAT
// d) optimises responses.
// Note that we can't trust the originator value in cache forwards, we therefore
// need to prevent someone from overwriting a valid originator->value1 mapping
// with an invalid originator->value2 mapping - that is we can't use uniqueness of
// originator
// a value can be "volatile" - this means that the cacher can ping the originator
// periodically and delete the value if it is dead
// the aim here is to
// 1) reduce ability for single contacts to spam the key while supporting up to 8
// contacts on a given IP (assuming NAT is being used)
// 2) stop one contact deleting or overwriting another contact's entry
// 3) support garbage collection for contacts that don't delete entries on exit
// TODO: we should enforce a max-values-per-sender restriction to stop a sender from spamming
// lots of keys - however, for a small DHT we need to be careful
protected void
add(
DHTDBValueImpl new_value )
{
// don't replace a closer cache value with a further away one. in particular
// we have to avoid the case where the original publisher of a key happens to
// be close to it and be asked by another node to cache it!
DHTTransportContact originator = new_value.getOriginator();
DHTTransportContact sender = new_value.getSender();
HashWrapper originator_id = new HashWrapper( originator.getID());
boolean direct = Arrays.equals( originator.getID(), sender.getID());
if ( direct ){
// direct contact from the originator is straight forward
addDirectValue( originator_id, new_value );
// remove any indirect values we might already have for this
Iterator it = indirect_originator_value_map.entrySet().iterator();
List to_remove = new ArrayList();
while( it.hasNext()){
Map.Entry entry = (Map.Entry)it.next();
HashWrapper existing_key = (HashWrapper)entry.getKey();
DHTDBValueImpl existing_value = (DHTDBValueImpl)entry.getValue();
if ( Arrays.equals( existing_value.getOriginator().getID(), originator.getID())){
to_remove.add( existing_key );
}
}
for (int i=0;i<to_remove.size();i++){
removeIndirectValue((HashWrapper)to_remove.get(i));
}
}else{
// not direct. if we have a value already for this originator then
// we drop the value as the originator originated one takes precedence
if ( direct_originator_map.get( originator_id ) != null ){
return;
}
// rule (b) - one entry per originator/value pair
HashWrapper originator_value_id = getOriginatorValueID( new_value );
DHTDBValueImpl existing_value = (DHTDBValueImpl)indirect_originator_value_map.get( originator_value_id );
if ( existing_value != null ){
addIndirectValue( originator_value_id, new_value );
//System.out.println( " replacing existing" );
}else{
// only add new values if not diversified
if ( diversification_state == DHT.DT_NONE ){
addIndirectValue( originator_value_id, new_value );
}
}
}
}
private HashWrapper
getOriginatorValueID(
DHTDBValueImpl value )
{
DHTTransportContact originator = value.getOriginator();
byte[] originator_id = originator.getID();
// relaxed this due to problems caused by multiple publishes by an originator
// with the same key but variant values (e.g. seed/peer counts). Seeing as we
// only accept cache-forwards from contacts that are "close" enough to us to
// be performing such a forward, the DOS possibilities here are limited (a nasty
// contact can only trash originator values for things it happens to be close to)
return( new HashWrapper( originator_id ));
/*
byte[] value_bytes = value.getValue();
byte[] x = new byte[originator_id.length + value_bytes.length];
System.arraycopy( originator_id, 0, x, 0, originator_id.length );
System.arraycopy( value_bytes, 0, x, originator_id.length, value_bytes.length );
HashWrapper originator_value_id = new HashWrapper( new SHA1Hasher().calculateHash( x ));
return( originator_value_id );
*/
}
protected void
addHit()
{
hits++;
}
protected int
getHits()
{
return( hits );
}
protected int
getIndirectSize()
{
return( indirect_data_size );
}
protected int
getDirectSize()
{
// our direct count includes local so remove that here
return( direct_data_size - local_size );
}
protected int
getLocalSize()
{
return( local_size );
}
protected DHTDBValueImpl[]
get(
DHTTransportContact by_who,
int max,
byte flags )
{
if ((flags & DHT.FLAG_STATS) != 0 ){
if ( adapter_key != null ){
try{
ByteArrayOutputStream baos = new ByteArrayOutputStream(64);
DataOutputStream dos = new DataOutputStream( baos );
adapter_key.serialiseStats( dos );
dos.close();
return(
new DHTDBValueImpl[]{
new DHTDBValueImpl(
SystemTime.getCurrentTime(),
baos.toByteArray(),
0,
db.getLocalContact(),
db.getLocalContact(),
true,
DHT.FLAG_STATS )});
}catch( Throwable e ){
Debug.printStackTrace(e);
}
}
return( new DHTDBValueImpl[0] );
}
List res = new ArrayList();
Set duplicate_check = new HashSet();
Map[] maps = new Map[]{ direct_originator_map, indirect_originator_value_map };
for (int i=0;i<maps.length;i++){
List keys_used = new ArrayList();
Map map = maps[i];
Iterator it = map.entrySet().iterator();
while( it.hasNext() && ( max==0 || res.size()< max )){
Map.Entry entry = (Map.Entry)it.next();
HashWrapper entry_key = (HashWrapper)entry.getKey();
DHTDBValueImpl entry_value = (DHTDBValueImpl)entry.getValue();
HashWrapper x = new HashWrapper( entry_value.getValue());
if ( duplicate_check.contains( x )){
continue;
}
duplicate_check.add( x );
// zero length values imply deleted values so don't return them
if ( entry_value.getValue().length > 0 ){
res.add( entry_value );
keys_used.add( entry_key );
}
}
// now update the access order so values get cycled
for (int j=0;j<keys_used.size();j++){
map.get( keys_used.get(j));
}
}
informRead( by_who );
DHTDBValueImpl[] v = new DHTDBValueImpl[res.size()];
res.toArray( v );
return( v );
}
protected DHTDBValueImpl
get(
DHTTransportContact originator )
{
// local get
HashWrapper originator_id = new HashWrapper( originator.getID());
DHTDBValueImpl res = (DHTDBValueImpl)direct_originator_map.get( originator_id );
return( res );
}
protected DHTDBValueImpl
remove(
DHTTransportContact originator )
{
// local remove
HashWrapper originator_id = new HashWrapper( originator.getID());
DHTDBValueImpl res = removeDirectValue( originator_id );
return( res );
}
protected int
getValueCount()
{
return( direct_originator_map.size() + indirect_originator_value_map.size());
}
protected Iterator
getValues()
{
return( new valueIterator( true, true ));
}
protected Iterator
getDirectValues()
{
return( new valueIterator( true, false ));
}
protected Iterator
getIndirectValues()
{
return( new valueIterator( false, true ));
}
protected byte
getDiversificationType()
{
return( diversification_state );
}
protected void
addDirectValue(
HashWrapper value_key,
DHTDBValueImpl value )
{
DHTDBValueImpl old = (DHTDBValueImpl)direct_originator_map.put( value_key, value );
if ( old != null ){
int old_version = old.getVersion();
int new_version = value.getVersion();
if ( old_version != -1 && new_version != -1 && old_version >= new_version ){
if ( old_version == new_version ){
if ( TRACE_ADDS ){
System.out.println( "addDirect[reset]:" + old.getString() + "/" + value.getString());
}
old.reset(); // update store time as this means we don't need to republish
// as someone else has just done it
}else{
// its important to ignore old versions as a peer's increasing version sequence may
// have been reset and if this is the case we want the "future" values to timeout
if ( TRACE_ADDS ){
System.out.println( "addDirect[ignore]:" + old.getString() + "/" + value.getString());
}
}
// put the old value back!
direct_originator_map.put( value_key, old );
return;
}
if ( TRACE_ADDS ){
System.out.println( "addDirect:" + old.getString() + "/" + value.getString());
}
direct_data_size -= old.getValue().length;
if ( old.isLocal()){
local_size -= old.getValue().length;
}
}else{
if ( TRACE_ADDS ){
System.out.println( "addDirect:[new]" + value.getString());
}
}
direct_data_size += value.getValue().length;
if ( value.isLocal()){
local_size += value.getValue().length;
}
if ( old == null ){
informAdded( value );
}else{
informUpdated( old, value );
}
}
protected DHTDBValueImpl
removeDirectValue(
HashWrapper value_key )
{
DHTDBValueImpl old = (DHTDBValueImpl)direct_originator_map.remove( value_key );
if ( old != null ){
direct_data_size -= old.getValue().length;
if ( old.isLocal()){
local_size -= old.getValue().length;
}
informDeleted( old );
}
return( old );
}
protected void
addIndirectValue(
HashWrapper value_key,
DHTDBValueImpl value )
{
DHTDBValueImpl old = (DHTDBValueImpl)indirect_originator_value_map.put( value_key, value );
if ( old != null ){
// discard updates that are older than current value
int old_version = old.getVersion();
int new_version = value.getVersion();
if ( old_version != -1 && new_version != -1 && old_version >= new_version ){
if ( old_version == new_version ){
if ( TRACE_ADDS ){
System.out.println( "addIndirect[reset]:" + old.getString() + "/" + value.getString());
}
old.reset(); // update store time as this means we don't need to republish
// as someone else has just done it
}else{
if ( TRACE_ADDS ){
System.out.println( "addIndirect[ignore]:" + old.getString() + "/" + value.getString());
}
}
// put the old value back!
indirect_originator_value_map.put( value_key, old );
return;
}
// vague backwards compatability - if the creation date of the "new" value is significantly
// less than the old then we ignore it (given that creation date is adjusted for time-skew you can
// see the problem with this approach...)
if ( old_version == -1 || new_version == -1 ){
if ( old.getCreationTime() > value.getCreationTime() + 30000 ){
if ( TRACE_ADDS ){
System.out.println( "backward compat: ignoring store: " + old.getString() + "/" + value.getString());
}
// put the old value back!
indirect_originator_value_map.put( value_key, old );
return;
}
}
if ( TRACE_ADDS ){
System.out.println( "addIndirect:" + old.getString() + "/" + value.getString());
}
indirect_data_size -= old.getValue().length;
if ( old.isLocal()){
local_size -= old.getValue().length;
}
}else{
if ( TRACE_ADDS ){
System.out.println( "addIndirect:[new]" + value.getString());
}
}
indirect_data_size += value.getValue().length;
if ( value.isLocal()){
local_size += value.getValue().length;
}
if ( old == null ){
informAdded( value );
}else{
informUpdated( old, value );
}
}
protected void
removeIndirectValue(
HashWrapper value_key )
{
DHTDBValueImpl old = (DHTDBValueImpl)indirect_originator_value_map.remove( value_key );
if ( old != null ){
indirect_data_size -= old.getValue().length;
if ( old.isLocal()){
local_size -= old.getValue().length;
}
informDeleted( old );
}
}
protected void
destroy()
{
try{
if ( adapter_key != null ){
Iterator it = getValues();
while( it.hasNext()){
it.next();
it.remove();
}
db.getAdapter().keyDeleted( adapter_key );
}
}catch( Throwable e ){
Debug.printStackTrace(e);
}
}
private void
informDeleted(
DHTDBValueImpl value )
{
boolean direct =
(!value.isLocal())&&
Arrays.equals( value.getOriginator().getID(), value.getSender().getID());
if ( direct ){
removeFromBloom( value );
}
try{
if ( adapter_key != null ){
db.getAdapter().valueDeleted( adapter_key, value );
diversification_state = adapter_key.getDiversificationType();
}
}catch( Throwable e ){
Debug.printStackTrace(e);
}
}
private void
informAdded(
DHTDBValueImpl value )
{
boolean direct =
(!value.isLocal()) &&
Arrays.equals( value.getOriginator().getID(), value.getSender().getID());
if ( direct ){
addToBloom( value );
}
try{
if ( adapter_key != null ){
db.getAdapter().valueAdded( adapter_key, value );
diversification_state = adapter_key.getDiversificationType();
}
}catch( Throwable e ){
Debug.printStackTrace(e);
}
}
private void
informUpdated(
DHTDBValueImpl old_value,
DHTDBValueImpl new_value)
{
boolean old_direct =
(!old_value.isLocal()) &&
Arrays.equals( old_value.getOriginator().getID(), old_value.getSender().getID());
boolean new_direct =
(!new_value.isLocal()) &&
Arrays.equals( new_value.getOriginator().getID(), new_value.getSender().getID());
if ( new_direct && !old_direct ){
addToBloom( new_value );
}
try{
if ( adapter_key != null ){
db.getAdapter().valueUpdated( adapter_key, old_value, new_value );
diversification_state = adapter_key.getDiversificationType();
}
}catch( Throwable e ){
Debug.printStackTrace(e);
}
}
private void
informRead(
DHTTransportContact contact ){
try{
if ( adapter_key != null && contact != null ){
db.getAdapter().keyRead( adapter_key, contact );
diversification_state = adapter_key.getDiversificationType();
}
}catch( Throwable e ){
Debug.printStackTrace(e);
}
}
protected void
addToBloom(
DHTDBValueImpl value )
{
// we don't check for flooding on indirect stores as this could be used to force a
// direct store to be bounced (flood a node with indirect stores before the direct
// store occurs)
DHTTransportContact originator = value.getOriginator();
int hit_count = ip_count_bloom_filter.add( originator.getAddress().getAddress().getAddress());
if ( DHTLog.LOCAL_BLOOM_TRACE ){
System.out.println( "direct local add from " + originator.getAddress() + ", hit count = " + hit_count );
}
// allow up to 10% bloom filter utilisation
if ( ip_count_bloom_filter.getSize() / ip_count_bloom_filter.getEntryCount() < 10 ){
rebuildIPBloomFilter( true );
}
if ( hit_count >= 15 ){
db.banContact( originator, "local flood on '" + DHTLog.getFullString( key.getBytes()) + "'" );
}
}
protected void
removeFromBloom(
DHTDBValueImpl value )
{
DHTTransportContact originator = value.getOriginator();
int hit_count = ip_count_bloom_filter.remove( originator.getAddress().getAddress().getAddress());
if ( DHTLog.LOCAL_BLOOM_TRACE ){
System.out.println( "direct local remove from " + originator.getAddress() + ", hit count = " + hit_count );
}
}
protected void
rebuildIPBloomFilter(
boolean increase_size )
{
BloomFilter new_filter;
if ( increase_size ){
new_filter = BloomFilterFactory.createAddRemove4Bit( ip_count_bloom_filter.getSize() + IP_COUNT_BLOOM_SIZE_INCREASE_CHUNK );
}else{
new_filter = BloomFilterFactory.createAddRemove4Bit( ip_count_bloom_filter.getSize());
}
try{
// only do flood prevention on direct stores as we can't trust the originator
// details for indirect and this can be used to DOS a direct store later
Iterator it = getDirectValues();
int max_hits = 0;
while( it.hasNext()){
DHTDBValueImpl val = (DHTDBValueImpl)it.next();
if ( !val.isLocal()){
// logger.log( " adding " + val.getOriginator().getAddress());
int hits = new_filter.add( val.getOriginator().getAddress().getAddress().getAddress());
if ( hits > max_hits ){
max_hits = hits;
}
}
}
if ( DHTLog.LOCAL_BLOOM_TRACE ){
db.log( "Rebuilt local IP bloom filter, size = " + new_filter.getSize() + ", entries =" + new_filter.getEntryCount()+", max hits = " + max_hits );
}
}finally{
ip_count_bloom_filter = new_filter;
}
}
protected class
valueIterator
implements Iterator
{
private List maps = new ArrayList(2);
private int map_index = 0;
private Map map;
private Iterator it;
private DHTDBValueImpl value;
protected
valueIterator(
boolean direct,
boolean indirect )
{
if ( direct ){
maps.add( direct_originator_map );
}
if ( indirect ){
maps.add( indirect_originator_value_map );
}
}
public boolean
hasNext()
{
if ( it != null && it.hasNext()){
return( true );
}
while( map_index < maps.size() ){
map = (Map)maps.get(map_index++);
it = map.values().iterator();
if ( it.hasNext()){
return( true );
}
}
return( false );
}
public Object
next()
{
if ( hasNext()){
value = (DHTDBValueImpl)it.next();
return( value );
}
throw( new NoSuchElementException());
}
public void
remove()
{
if ( it == null ){
throw( new IllegalStateException());
}
if ( value != null ){
if( value.isLocal()){
local_size -= value.getValue().length;
}
if ( map == indirect_originator_value_map ){
indirect_data_size -= value.getValue().length;
}else{
direct_data_size -= value.getValue().length;
}
// remove before informing
it.remove();
informDeleted( value );
}else{
it.remove();
}
}
}
}
The table below shows all metrics for DHTDBMapping.java.
| Metric | Value | Description | |
|---|---|---|---|
| BLOCKS | 135.00 | Number of blocks | |
| BLOCK_COMMENT | 33.00 | Number of block comment lines | |
| COMMENTS | 114.00 | Comment lines | |
| COMMENT_DENSITY | 0.27 | Comment density | |
| COMPARISONS | 99.00 | Number of comparison operators | |
| CYCLOMATIC | 129.00 | Cyclomatic complexity | |
| DECL_COMMENTS | 14.00 | Comments in declarations | |
| DOC_COMMENT | 4.00 | Number of javadoc comment lines | |
| ELOC | 429.00 | Effective lines of code | |
| EXEC_COMMENTS | 28.00 | Comments in executable code | |
| EXITS | 73.00 | Procedure exits | |
| FUNCTIONS | 34.00 | Number of function declarations | |
| HALSTEAD_DIFFICULTY | 102.16 | Halstead difficulty | |
| HALSTEAD_EFFORT | 0.00 | Halstead effort | |
| INTERFACE_COMPLEXITY | 71.00 | Interface complexity | |
| JAVA0001 | 0.00 | JAVA0001 Package name does not contain only lower case letters | |
| JAVA0002 | 0.00 | JAVA0002 Package name does not begin with a top level domain name or country code | |
| JAVA0003 | 0.00 | JAVA0003 Minimize use of on-demand (.*) imports | |
| JAVA0004 | 0.00 | JAVA0004 Unnecessary import from java.lang | |
| JAVA0005 | 0.00 | JAVA0005 Imports not in specified order | |
| JAVA0006 | 0.00 | JAVA0006 Empty finally block | |
| JAVA0007 | 0.00 | JAVA0007 Should not declare public field | |
| JAVA0008 | 0.00 | JAVA0008 Empty catch block | |
| JAVA0009 | 0.00 | JAVA0009 Protected member in final class | |
| JAVA0010 | 0.00 | JAVA0010 Non-instantiable class does not contain a non-private static member | |
| JAVA0011 | 0.00 | JAVA0011 Abstract class does not contain an abstract method | |
| JAVA0012 | 0.00 | JAVA0012 Non-constructor method with same name as declaring class | |
| JAVA0013 | 0.00 | JAVA0013 Non-blank final field is not static | |
| JAVA0014 | 0.00 | JAVA0014 Class with only static members has non-private constructor | |
| JAVA0015 | 0.00 | JAVA0015 Package class contains public nested type | |
| JAVA0016 | 0.00 | JAVA0016 Abstract class contains public constructor | |
| JAVA0017 | 0.00 | JAVA0017 Class name does not have required form | |
| JAVA0018 | 0.00 | JAVA0018 Method name does not have required form | |
| JAVA0019 | 0.00 | JAVA0019 Interface name does not have required form | |
| JAVA0020 | 0.00 | JAVA0020 Field name does not have required form | |
| JAVA0021 | 0.00 | JAVA0021 Interface method name does not have required form | |
| JAVA0022 | 0.00 | JAVA0022 Static final field name does not have required form | |
| JAVA0023 | 0.00 | JAVA0023 Empty finalize method | |
| JAVA0024 | 0.00 | JAVA0024 Empty class | |
| JAVA0025 | 0.00 | JAVA0025 Method override is empty | |
| JAVA0026 | 0.00 | JAVA0026 Finalize method with parameters | |
| JAVA0029 | 0.00 | JAVA0029 Private method not used | |
| JAVA0030 | 0.00 | JAVA0030 Private field not used | |
| JAVA0031 | 0.00 | JAVA0031 Case statement not properly closed | |
| JAVA0032 | 0.00 | JAVA0032 Switch statement missing default | |
| JAVA0033 | 0.00 | JAVA0033 default: not last case in switch statement | |
| JAVA0034 | 0.00 | JAVA0034 Missing braces in if statement | |
| JAVA0035 | 0.00 | JAVA0035 Missing braces in for statement | |
| JAVA0036 | 0.00 | JAVA0036 Missing braces in while statement | |
| JAVA0038 | 0.00 | JAVA0038 Non-case label in switch statement | |
| JAVA0039 | 0.00 | JAVA0039 Break statement with label | |
| JAVA0040 | 0.00 | JAVA0040 Switch statement contains N cases (maximum: M) | |
| JAVA0041 | 0.00 | JAVA0041 Nested synchronized block | |
| JAVA0042 | 0.00 | JAVA0042 Empty synchronized statement | |
| JAVA0043 | 0.00 | JAVA0043 Inner class does not use outer class | |
| JAVA0044 | 0.00 | JAVA0044 Serializable class with no instance variables | |
| JAVA0045 | 0.00 | JAVA0045 Serializable class with only transient fields | |
| JAVA0046 | 0.00 | JAVA0046 Name of class not derived from Exception ends with 'Exception' | |
| JAVA0047 | 0.00 | JAVA0047 Serializable class derives from invalid base class | |
| JAVA0048 | 0.00 | JAVA0048 Name of class derived from Exception does not end with 'Exception' | |
| JAVA0049 | 0.00 | JAVA0049 Nested block at depth N (maximum: M) | |
| JAVA0050 | 0.00 | JAVA0050 Class derives from java.lang.Error | |
| JAVA0051 | 0.00 | JAVA0051 Class derives from java.lang.RuntimeException | |
| JAVA0052 | 0.00 | JAVA0052 Class derives from java.lang.Throwable | |
| JAVA0053 | 0.00 | JAVA0053 Unused label | |
| JAVA0054 | 0.00 | JAVA0054 Inheritance depth N exceeds maximum M | |
| JAVA0055 | 0.00 | JAVA0055 Class should be interface | |
| JAVA0056 | 0.00 | JAVA0056 Unnecessary abstract modifier for interface or annotation | |
| JAVA0057 | 0.00 | JAVA0057 Unnecessary default constructor | |
| JAVA0058 | 0.00 | JAVA0058 Constructor calls super() | |
| JAVA0059 | 0.00 | JAVA0059 Method override only calls super() | |
| JAVA0061 | 0.00 | JAVA0061 Inaccessible member in anonymous class | |
| JAVA0062 | 0.00 | JAVA0062 Public class missing public member or protected constructor | |
| JAVA0063 | 0.00 | JAVA0063 Identifier name should not contain '$' | |
| JAVA0064 | 0.00 | JAVA0064 N variations of identifier name (maximum: M) | |
| JAVA0065 | 0.00 | JAVA0065 Unnecessary final modifier for method in final class | |
| JAVA0066 | 0.00 | JAVA0066 Unnecessary modifier for interface nested type | |
| JAVA0067 | 0.00 | JAVA0067 Array descriptor on identifier name | |
| JAVA0068 | 0.00 | JAVA0068 Modifiers not declared in recommended order | |
| JAVA0071 | 0.00 | JAVA0071 Strings compared with == | |
| JAVA0073 | 0.00 | JAVA0073 Integer division in floating-point context | |
| JAVA0074 | 0.00 | JAVA0074 Use of Object.notify() | |
| JAVA0075 | 0.00 | JAVA0075 Method parameter hides field | |
| JAVA0076 | 4.00 | JAVA0076 Use of magic number | |
| JAVA0077 | 0.00 | JAVA0077 Private field not used in declaring class | |
| JAVA0078 | 0.00 | JAVA0078 Floating point values compared with == | |
| JAVA0079 | 0.00 | JAVA0079 Use of instance to reference static member | |
| JAVA0080 | 0.00 | JAVA0080 Import declaration not used | |
| JAVA0081 | 0.00 | JAVA0081 Boolean literal in comparison | |
| JAVA0082 | 0.00 | JAVA0082 Unnecessary widening cast | |
| JAVA0083 | 0.00 | JAVA0083 Unnecessary instanceof test | |
| JAVA0084 | 0.00 | JAVA0084 Should use compound assignment operator | |
| JAVA0085 | 0.00 | JAVA0085 Use of sun.* class | |
| JAVA0087 | 0.00 | JAVA0087 Use of Thread.sleep() | |
| JAVA0089 | 0.00 | JAVA0089 Use of restricted package | |
| JAVA0092 | 0.00 | JAVA0092 Use of restricted type | |
| JAVA0093 | 0.00 | JAVA0093 Redundant assignment | |
| JAVA0094 | 0.00 | JAVA0094 Field hides a superclass field | |
| JAVA0095 | 0.00 | JAVA0095 Uninitialized private field | |
| JAVA0096 | 0.00 | JAVA0096 Field in nested class hides outer field | |
| JAVA0098 | 0.00 | JAVA0098 Minimize use of implicit field initializers | |
| JAVA0100 | 1.00 | JAVA0100 Class contains N non-final fields (maximum: M) | |
| JAVA0101 | 0.00 | JAVA0101 Unnecessary modifier for field in interface | |
| JAVA0102 | 0.00 | JAVA0102 Last statement in finalize() not super.finalize() | |
| JAVA0103 | 0.00 | JAVA0103 Explicit call to finalize() | |
| JAVA0104 | 0.00 | JAVA0104 finalize() only calls super.finalize() | |
| JAVA0105 | 0.00 | JAVA0105 Duplicate import declaration | |
| JAVA0106 | 0.00 | JAVA0106 Unnecessary import from current package | |
| JAVA0108 | 0.00 | JAVA0108 Incorrect javadoc: no @param tag for 'parameter' | |
| JAVA0109 | 0.00 | JAVA0109 Incorrect javadoc: no parameter 'parameter' | |
| JAVA0110 | 0.00 | JAVA0110 Incorrect javadoc: no @return tag | |
| JAVA0111 | 0.00 | JAVA0111 Incorrect javadoc: @return tag for void method | |
| JAVA0112 | 0.00 | JAVA0112 Incorrect javadoc: no exception 'exception' in throws | |
| JAVA0113 | 0.00 | JAVA0113 Incorrect javadoc: no @author tag | |
| JAVA0114 | 1.00 | JAVA0114 Incorrect javadoc: no @version tag | |
| JAVA0115 | 0.00 | JAVA0115 Incorrect javadoc: no @throws or @exception tag for 'exception' | |
| JAVA0116 | 0.00 | JAVA0116 Missing javadoc: field 'field' | |
| JAVA0117 | 26.00 | JAVA0117 Missing javadoc: method 'method' | |
| JAVA0118 | 0.00 | JAVA0118 Missing javadoc: type 'type' | |
| JAVA0119 | 0.00 | JAVA0119 Control variable changed within body of for loop | |
| JAVA0123 | 0.00 | JAVA0123 Use all three components of for loop | |
| JAVA0125 | 0.00 | JAVA0125 Continue statement with label | |
| JAVA0126 | 0.00 | JAVA0126 Method declares unchecked exception in throws | |
| JAVA0128 | 0.00 | JAVA0128 Public constructor in non-public class | |
| JAVA0130 | 1.00 | JAVA0130 Non-static method does not use instance fields | |
| JAVA0131 | 0.00 | JAVA0131 Compatible method does not override base | |
| JAVA0132 | 0.00 | JAVA0132 Method overload with compatible signature | |
| JAVA0133 | 0.00 | JAVA0133 Non-synchronized method overrides synchronized method | |
| JAVA0135 | 0.00 | JAVA0135 Only one of Object.equals and Object.hashCode defined: missing 'method' | |
| JAVA0136 | 1.00 | JAVA0136 N methods defined in class (maximum: M) | |
| JAVA0137 | 0.00 | JAVA0137 Non-abstract class missing constructor | |
| JAVA0138 | 0.00 | JAVA0138 N parameters defined for method (maximum: M) | |
| JAVA0139 | 0.00 | JAVA0139 Definition of main other than public static void main(java.lang.String[]) | |
| JAVA0141 | 0.00 | JAVA0141 Unnecessary modifier for method in interface | |
| JAVA0143 | 0.00 | JAVA0143 Synchronized method | |
| JAVA0144 | 2.00 | JAVA0144 Line exceeds maximum M characters | |
| JAVA0145 | 2770.00 | JAVA0145 Tab character used in source file | |
| JAVA0150 | 0.00 | JAVA0150 java.lang.Error (or subclass) thrown | |
| JAVA0153 | 0.00 | JAVA0153 Inefficient conversion of integer to string | |
| JAVA0159 | 0.00 | JAVA0159 Inefficient conversion of string to integer | |
| JAVA0160 | 0.00 | JAVA0160 Method does not throw specified exception | |
| JAVA0161 | 0.00 | JAVA0161 Conditional wait() not in loop | |
| JAVA0163 | 0.00 | JAVA0163 Empty statement | |
| JAVA0165 | 0.00 | JAVA0165 Conflicting return statement in finally block | |
| JAVA0166 | 7.00 | JAVA0166 Generic exception caught | |
| JAVA0167 | 0.00 | JAVA0167 ThreadDeath not rethrown | |
| JAVA0169 | 0.00 | JAVA0169 Unnecessary catch block: exception 'exception' | |
| JAVA0170 | 7.00 | JAVA0170 Caught exception not derived from java.lang.Exception | |
| JAVA0171 | 0.00 | JAVA0171 Unused local variable | |
| JAVA0173 | 0.00 | JAVA0173 Unused method parameter | |
| JAVA0174 | 0.00 | JAVA0174 Assigned local variable never used | |
| JAVA0175 | 0.00 | JAVA0175 Successive assignment to variable | |
| JAVA0176 | 0.00 | JAVA0176 Local variable name does not have required form | |
| JAVA0177 | 1.00 | JAVA0177 Variable declaration missing initializer | |
| JAVA0179 | 1.00 | JAVA0179 Local variable hides visible field | |
| JAVA0233 | 0.00 | JAVA0233 Definition of serialVersionUID other than 'private static final long serialVersionUID' | |
| JAVA0234 | 0.00 | JAVA0234 Class is Serializable but does not define serialVersionUID | |
| JAVA0235 | 0.00 | JAVA0235 Class defines serialVersionUID but does not implement Serializable | |
| JAVA0236 | 0.00 | JAVA0236 Attempt to clone an object which does not implement Cloneable | |
| JAVA0237 | 0.00 | JAVA0237 Class implements Cloneable but does not have public clone method | |
| JAVA0238 | 0.00 | JAVA0238 Clone method does not call super.clone() | |
| JAVA0239 | 0.00 | JAVA0239 Class declares 'readObject' or 'writeObject' but does not implement Serializable | |
| JAVA0240 | 0.00 | JAVA0240 Serializable class which declares readObject or writeObject but not both | |
| JAVA0241 | 0.00 | JAVA0241 'readObject' or 'writeObject' should be declared private in Serializable class | |
| JAVA0242 | 0.00 | JAVA0242 Transient field in non-Serializable class | |
| JAVA0243 | 0.00 | JAVA0243 'readResolve' or 'writeReplace' should be declared private or protected | |
| JAVA0244 | 0.00 | JAVA0244 Field or method name in subclass differs only by case from inherited field or method | |
| JAVA0245 | 0.00 | JAVA0245 JUnit TestCase with non-trivial constructor | |
| JAVA0246 | 0.00 | JAVA0246 JUnit assertXXX statement missing message parameter | |
| JAVA0247 | 0.00 | JAVA0247 JUnit 'setUp()' and 'tearDown()' should call super method | |
| JAVA0248 | 0.00 | JAVA0248 JUnit method 'setUp' or 'tearDown' with incorrect signature | |
| JAVA0249 | 0.00 | JAVA0249 JUnit TestCase 'suite()' should be declared static | |
| JAVA0250 | 0.00 | JAVA0250 JUnit TestCase declares testXXX method with incorrect signature | |
| JAVA0251 | 0.00 | JAVA0251 Use '%n' for line breaks in printf/format for platform independence | |
| JAVA0252 | 0.00 | JAVA0252 'enum' is a Java 1.5 reserved word | |
| JAVA0253 | 0.00 | JAVA0253 Not all enum constants consumed in switch statement | |
| JAVA0254 | 3.00 | JAVA0254 Use enhanced for loop construct instead of Iterator | |
| JAVA0255 | 0.00 | JAVA0255 Result of method invocation not used | |
| JAVA0256 | 0.00 | JAVA0256 Assignment of external collection/array to field | |
| JAVA0257 | 0.00 | JAVA0257 Use of 'Constant Interface' anti-pattern | |
| JAVA0258 | 1.00 | JAVA0258 Implement Iterable for foreach compatibility | |
| JAVA0259 | 0.00 | JAVA0259 Return of collection/array field | |
| JAVA0260 | 0.00 | JAVA0260 Use 'enum' instead of Enumerated Type pattern | |
| JAVA0261 | 0.00 | JAVA0261 Use specialized Enum collection types | |
| JAVA0262 | 0.00 | JAVA0262 Use of char in integer context | |
| JAVA0263 | 0.00 | JAVA0263 Long literal ends with 'l' instead of 'L' | |
| JAVA0264 | 0.00 | JAVA0264 Integer math in long context - check for overflow | |
| JAVA0265 | 0.00 | JAVA0265 Use of Throwable.printStackTrace() | |
| JAVA0266 | 11.00 | JAVA0266 Use of System.out | |
| JAVA0267 | 0.00 | JAVA0267 Use of System.err | |
| JAVA0269 | 0.00 | JAVA0269 Contents of StringBuffer never used | |
| JAVA0270 | 1.00 | JAVA0270 Use Java 5.0 enhanced for loop construct to iterate over all elements in an array | |
| JAVA0271 | 0.00 | JAVA0271 Minimize use of on-demand (.*) static imports | |
| JAVA0272 | 0.00 | JAVA0272 Thread.run() called | |
| JAVA0273 | 0.00 | JAVA0273 Non-final derivative of Thread calls start() in constructor | |
| JAVA0274 | 0.00 | JAVA0274 Serializable class has a synchronized readObject() | |
| JAVA0275 | 0.00 | JAVA0275 Serializable class has a synchronized writeObject() and no other synchronized methods | |
| JAVA0276 | 0.00 | JAVA0276 Unnecessary use of String constructor | |
| JAVA0277 | 0.00 | JAVA0277 Iterator.next() implementation does not throw NoSuchElementException | |
| JAVA0278 | 0.00 | JAVA0278 Unnecessary use of Boolean constructor | |
| JAVA0279 | 0.00 | JAVA0279 Serialization method readObject or readObjectNoData calls an overridable method | |
| JAVA0280 | 0.00 | JAVA0280 IllegalMonitorStateException caught | |
| JAVA0281 | 0.00 | JAVA0281 Iterator.next() not called in loop | |
| JAVA0282 | 0.00 | JAVA0282 Call to Iterator.next() in loop which does not test Iterator.hasNext() | |
| JAVA0283 | 1.00 | JAVA0283 Control variable not updated in loop body | |
| JAVA0284 | 0.00 | JAVA0284 Explicit garbage collection | |
| JAVA0285 | 0.00 | JAVA0285 Dereference of potentially null variable | |
| JAVA0286 | 0.00 | JAVA0286 Dereference of null variable | |
| JAVA0287 | 0.00 | JAVA0287 Unnecessary null check | |
| JAVA0288 | 0.00 | JAVA0288 Inconsistent null check | |
| LINES | 1004.00 | Number of lines in the source file | |
| LINE_COMMENT | 77.00 | Number of line comments | |
| LOC | 582.00 | Lines of code | |
| LOGICAL_LINES | 219.00 | Number of statements | |
| LOOPS | 10.00 | Number of loops | |
| NEST_DEPTH | 5.00 | Maximum nesting depth | |
| OPERANDS | 1091.00 | Number of operands | |
| OPERATORS | 2275.00 | Number of operators | |
| PARAMS | 27.00 | Number of formal parameter declarations | |
| PROGRAM_LENGTH | 3366.00 | Halstead program length | |
| PROGRAM_VOCAB | 336.00 | Halstead program vocabulary | |
| PROGRAM_VOLUME | 0.00 | Halstead program volume | |
| RETURNS | 44.00 | Number of return points from functions | |
| SIZE | 23286.00 | Size of the file in bytes | |
| UNIQUE_OPERANDS | 283.00 | Number of unique operands | |
| UNIQUE_OPERATORS | 53.00 | Number of unique operators | |
| WHITESPACE | 308.00 | Number of whitespace lines | |