BTreePostCommit.java
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|---|---|---|
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org.apache.derby.impl.store.access.btree |
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Apache Derby |
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 |  |
| EXEC_COMMENTS | Comments in executable code | |
| JAVA0034 | JAVA0034 Missing braces in if statement | |
| SIZE | Size of the file in bytes | |
| JAVA0049 | JAVA0049 Nested block at depth N (maximum: M) | |
| JAVA0266 | JAVA0266 Use of System.out | |
| NEST_DEPTH | Maximum nesting depth | |
| COMMENTS | Comment lines | |
| JAVA0130 | JAVA0130 Non-static method does not use instance fields | |
| JAVA0117 | JAVA0117 Missing javadoc: method 'method' | |
| LINES | Number of lines in the source file | |
| PROGRAM_VOLUME | Halstead program volume | |
| JAVA0174 | JAVA0174 Assigned local variable never used | |
| RETURNS | Number of return points from functions | |
| JAVA0126 | JAVA0126 Method declares unchecked exception in throws | |
| UNIQUE_OPERATORS | Number of unique operators | |
| FUNCTIONS | Number of function declarations | |
| LOOPS | Number of loops | |
| JAVA0110 | JAVA0110 Incorrect javadoc: no @return tag | |
| JAVA0145 | JAVA0145 Tab character used in source file | |
/*
Derby - Class org.apache.derby.impl.store.access.btree.BTreePostCommit
Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements. See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to you under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package org.apache.derby.impl.store.access.btree;
import org.apache.derby.iapi.services.context.ContextManager;
import org.apache.derby.iapi.services.daemon.Serviceable;
import org.apache.derby.iapi.services.sanity.SanityManager;
import org.apache.derby.iapi.error.StandardException;
import org.apache.derby.iapi.store.access.AccessFactory;
import org.apache.derby.iapi.store.access.AccessFactoryGlobals;
import org.apache.derby.iapi.store.access.ConglomerateController;
import org.apache.derby.iapi.store.access.DynamicCompiledOpenConglomInfo;
import org.apache.derby.iapi.store.access.RowUtil;
import org.apache.derby.iapi.store.access.TransactionController;
import org.apache.derby.iapi.store.access.conglomerate.LogicalUndo;
import org.apache.derby.iapi.store.access.conglomerate.TransactionManager;
import org.apache.derby.iapi.store.raw.ContainerHandle;
import org.apache.derby.iapi.store.raw.FetchDescriptor;
import org.apache.derby.iapi.store.raw.LockingPolicy;
import org.apache.derby.iapi.store.raw.Page;
import org.apache.derby.iapi.store.raw.RecordHandle;
import org.apache.derby.iapi.types.DataValueDescriptor;
import org.apache.derby.iapi.reference.SQLState;
/**
The BTreePostCommit class implements the Serviceable protocol.
In it's role as a Serviceable object, it stores the state necessary to
find a page in a btree that may have committed delete's to reclaim.
In it's role as a PostCommitProcessor it looks up the page described, and
reclaims space in the btree. It first trys to clean up any deleted commits
on the page. It then will shrink the tree if it is going to delete all
rows from the page (RESOLVE - not done yet).
**/
class BTreePostCommit implements Serviceable
{
private AccessFactory access_factory = null;
private long page_number = ContainerHandle.INVALID_PAGE_NUMBER;
protected BTree btree = null;
/* Constructors for This class: */
BTreePostCommit(
AccessFactory access_factory,
BTree btree,
long input_page_number)
{
this.access_factory = access_factory;
this.btree = btree;
this.page_number = input_page_number;
}
/* Private/Protected methods of This class: */
/* Public Methods of This class: */
/* Public Methods of Serviceable class: */
/**
* The urgency of this post commit work.
* <p>
* This determines where this Serviceable is put in the post commit
* queue. Post commit work in the btree can be safely delayed until there
* is not user work to do.
*
* @return false, this work should not be serviced ASAP
**/
public boolean serviceASAP()
{
return(true);
}
// @return true, if this work needs to be done on a user thread immediately
public boolean serviceImmediately()
{
return false;
}
private final void doShrink(
OpenBTree open_btree,
DataValueDescriptor[] shrink_row)
throws StandardException
{
ControlRow root = null;
/*
System.out.println(
"Calling shrink on tree with levels = " +
open_btree.getHeight() + "\n");
*/
// Get the root page back, and perform a split following the
// to-be-inserted key. The split releases the root page latch.
root = ControlRow.get(open_btree, BTree.ROOTPAGEID);
root.shrinkFor(open_btree, shrink_row);
root = null;
// on return from shrinkFor the root pointer is invalid. The
// latch has been released, the root page may have changed from
// a branch to a leaf.
return;
}
/**
* Open index for either table level or row level update.
* <p>
* @param lock_level For table level use TransactionManager.MODE_TABLE,
* for row level use TransactionManager.MODE_RECORD
* @param lock_mode For table level use LockingPolicy.MODE_CONTAINER,
* for row level use LockingPolicy.MODE_RECORD
*
* @exception StandardException Standard exception policy.
**/
private final OpenBTree openIndex(
TransactionManager internal_xact,
int lock_level,
int lock_mode)
throws StandardException
{
OpenBTree open_btree = new OpenBTree();
ConglomerateController base_cc =
btree.lockTable(
internal_xact,
(ContainerHandle.MODE_FORUPDATE |
ContainerHandle.MODE_LOCK_NOWAIT),
lock_level,
TransactionController.ISOLATION_REPEATABLE_READ);
open_btree.init(
(TransactionManager) null,
internal_xact,
(ContainerHandle) null, // open the container
internal_xact.getRawStoreXact(),
false,
(ContainerHandle.MODE_FORUPDATE | ContainerHandle.MODE_LOCK_NOWAIT),
lock_level,
btree.getBtreeLockingPolicy(
internal_xact.getRawStoreXact(),
lock_level,
lock_mode,
TransactionController.ISOLATION_REPEATABLE_READ,
base_cc,
open_btree),
btree,
(LogicalUndo) null, // No logical undo necessry.
(DynamicCompiledOpenConglomInfo) null);
return(open_btree);
}
/**
* perform the work described in the postcommit work.
* <p>
* In this implementation the only work that can be executed by this
* post commit processor is this class itself.
* <p>
*
* @return Returns Serviceable.DONE when work has completed, or
* returns Serviceable.REQUEUE if work needs to be requeued.
*
* @param contextMgr the context manager started by the
* post commit daemon
*
* @exception StandardException Standard exception policy.
**/
public int performWork(ContextManager contextMgr)
throws StandardException
{
// requeue if work was not completed in this try because of locks
boolean requeue_work = false;
TransactionManager tc = (TransactionManager)
this.access_factory.getAndNameTransaction(
contextMgr, AccessFactoryGlobals.SYS_TRANS_NAME);
TransactionManager internal_xact = tc.getInternalTransaction();
if (SanityManager.DEBUG)
{
if (SanityManager.DEBUG_ON("verbose_btree_post_commit"))
System.out.println("starting internal xact\n");
}
OpenBTree open_btree = null;
try
{
// Get lock on base table.
// First attempt to get a table lock on the btree. This lock is
// requested NOWAIT to not impede normal operation on the table.
// If the lock were to wait then the current lock manager livelock
// algorithm would block all subsequent lock requests on this
// btree even if they are compatible with the current holder of
// the lock.
//
// If this lock is granted then:
// 1) deleted rows on the page can automatically be purged as
// they must be committed, otherwise lock would not have been
// granted.
// 2) if all rows from page are reclaimed then a structure shrink
// which requires table level lock can be executed.
//
open_btree =
openIndex(
internal_xact,
TransactionController.MODE_TABLE,
LockingPolicy.MODE_CONTAINER);
DataValueDescriptor[] shrink_key =
purgeCommittedDeletes(open_btree, this.page_number);
// RESOLVE (mikem) - move this call when doing row level locking.
if (shrink_key != null)
doShrink(open_btree, shrink_key);
open_btree.close();
}
catch (StandardException se)
{
// 2 kinds of errors here expected here. Either container not
// found or could not obtain lock (LOCK_TIMEOUT or DEADLOCK).
//
// It is possible by the time this post commit work gets scheduled
// that the container has been dropped and that the open container
// call will return null - in this case just return assuming no
// work to be done.
if (se.getMessageId().equals(SQLState.LOCK_TIMEOUT) ||
se.getMessageId().equals(SQLState.DEADLOCK))
{
// Could not get exclusive table lock, so try row level
// reclaim of just the rows on this page. No merge is
// attempted.
try
{
open_btree =
openIndex(
internal_xact,
TransactionController.MODE_RECORD,
LockingPolicy.MODE_RECORD);
purgeRowLevelCommittedDeletes(open_btree);
open_btree.close();
}
catch (StandardException se2)
{
if (se2.getMessageId().equals(SQLState.LOCK_TIMEOUT) ||
se2.getMessageId().equals(SQLState.DEADLOCK))
{
// Could not get intended exclusive table lock, so
// requeue and hope other user gives up table level
// lock soon. This should not be normal case.
requeue_work = true;
}
}
}
}
finally
{
internal_xact.commit();
internal_xact.destroy();
}
return(requeue_work ? Serviceable.REQUEUE : Serviceable.DONE);
}
private final DataValueDescriptor[] getShrinkKey(
OpenBTree open_btree,
ControlRow control_row,
int slot_no)
throws StandardException
{
DataValueDescriptor[] shrink_key =
open_btree.getConglomerate().createTemplate(
open_btree.getRawTran());
control_row.page.fetchFromSlot(
(RecordHandle) null,
slot_no, shrink_key,
(FetchDescriptor) null,
true);
return(shrink_key);
}
/**
* Reclaim space taken up by committed deleted rows.
* <p>
* This routine assumes it has been called by an internal transaction which
* has performed no work so far, and that it has an exclusive table lock.
* These assumptions mean that any deleted rows encountered must be from
* committed transactions (otherwise we could not have gotten the exclusive
* table lock).
* <p>
* RESOLVE (mikem) - under row locking this routine must do more work to
* determine a deleted row is a committed deleted row.
*
* @param open_btree The btree already opened.
* @param pageno The page number of the page to look for committed deletes.
*
* @exception StandardException Standard exception policy.
**/
private final DataValueDescriptor[] purgeCommittedDeletes(
OpenBTree open_btree,
long pageno)
throws StandardException
{
ControlRow control_row = null;
DataValueDescriptor[] shrink_key = null;
try
{
// The following can fail either if it can't get the latch or
// somehow the page requested no longer exists. In either case
// the post commit work will just skip it.
control_row = ControlRow.getNoWait(open_btree, pageno);
if (control_row != null)
{
Page page = control_row.page;
// The number records that can be reclaimed is:
// total recs - control row - recs_not_deleted
int num_possible_commit_delete =
page.recordCount() - 1 - page.nonDeletedRecordCount();
if (num_possible_commit_delete > 0)
{
// loop backward so that purges which affect the slot table
// don't affect the loop (ie. they only move records we
// have already looked at).
for (int slot_no = page.recordCount() - 1;
slot_no > 0;
slot_no--)
{
if (page.isDeletedAtSlot(slot_no))
{
if (page.recordCount() == 2)
{
// About to purge last row from page so
// remember the key so we can shrink the
// tree.
shrink_key = this.getShrinkKey(
open_btree, control_row, slot_no);
}
page.purgeAtSlot(slot_no, 1, true);
if (SanityManager.DEBUG)
{
if (SanityManager.DEBUG_ON(
"verbose_btree_post_commit"))
{
System.out.println(
"Purging row[" + slot_no + "]" +
"on page:" + pageno + ".\n");
}
}
}
}
}
if (page.recordCount() == 1)
{
if (SanityManager.DEBUG)
{
if (SanityManager.DEBUG_ON("verbose_btree_post_commit"))
{
System.out.println("Chance to shrink.\n");
}
}
}
}
else
{
if (SanityManager.DEBUG)
{
if (SanityManager.DEBUG_ON("verbose_btree_post_commit"))
{
System.out.println(
"Get No Wait returned null. page num = " + pageno +
"\n");
}
}
}
}
finally
{
if (control_row != null)
control_row.release();
}
return(shrink_key);
}
/**
* Attempt to reclaim committed deleted rows from the page with row locking.
* <p>
* Get exclusive latch on page, and then loop backward through
* page searching for deleted rows which are committed.
* This routine is called only from post commit processing so it will never
* see rows deleted by the current transaction.
* For each deleted row on the page
* it attempts to get an exclusive lock on the deleted row, NOWAIT.
* If it succeeds, and since this transaction did not delete the row then
* the row must have been deleted by a transaction which has committed, so
* it is safe to purge the row. It then purges the row from the page.
*
* @param open_btree The already open btree, which has been locked with IX
* table lock, to use to get latch on page.
*
* @exception StandardException Standard exception policy.
**/
private final void purgeRowLevelCommittedDeletes(
OpenBTree open_btree)
throws StandardException
{
LeafControlRow leaf = null;
try
{
// The following can fail, returning null, either if it can't get
// the latch or somehow the page requested no longer exists. In
// either case the post commit work will just skip it.
leaf = (LeafControlRow)
ControlRow.getNoWait(open_btree, page_number);
if (leaf == null)
return;
BTreeLockingPolicy btree_locking_policy =
open_btree.getLockingPolicy();
// The number records that can be reclaimed is:
// total recs - control row - recs_not_deleted
int num_possible_commit_delete =
leaf.page.recordCount() - 1 - leaf.page.nonDeletedRecordCount();
if ((num_possible_commit_delete > 0) &&
(btree_locking_policy.lockScanForReclaimSpace(leaf)))
{
DataValueDescriptor[] scratch_template =
open_btree.getRuntimeMem().get_template(
open_btree.getRawTran());
// Need to get an exclusive scan lock on the page before we can
// do any sort of purges, otherwise other concurrent scans would
// not work. If we can't get the lock NOWAIT, just give up on
// purging rows.
Page page = leaf.page;
// RowLocation column is in last column of template.
FetchDescriptor lock_fetch_desc =
RowUtil.getFetchDescriptorConstant(
scratch_template.length - 1);
// loop backward so that purges which affect the slot table
// don't affect the loop (ie. they only move records we
// have already looked at).
for (int slot_no = page.recordCount() - 1;
slot_no > 0;
slot_no--)
{
if (page.isDeletedAtSlot(slot_no))
{
// try to get an exclusive lock on the row, if we can
// then the row is a committed deleted row and it is
// safe to purge it.
if (btree_locking_policy.lockScanCommittedDeletedRow(
open_btree, leaf, scratch_template,
lock_fetch_desc, slot_no))
{
// the row is a committed deleted row, purge it.
page.purgeAtSlot(slot_no, 1, true);
}
}
}
}
}
finally
{
if (leaf != null)
leaf.release();
}
}
}
The table below shows all metrics for BTreePostCommit.java.
| Metric | Value | Description | |
|---|---|---|---|
| BLOCKS | 38.00 | Number of blocks | |
| BLOCK_COMMENT | 29.00 | Number of block comment lines | |
| COMMENTS | 175.00 | Comment lines | |
| COMMENT_DENSITY | 0.85 | Comment density | |
| COMPARISONS | 29.00 | Number of comparison operators | |
| CYCLOMATIC | 39.00 | Cyclomatic complexity | |
| DECL_COMMENTS | 12.00 | Comments in declarations | |
| DOC_COMMENT | 82.00 | Number of javadoc comment lines | |
| ELOC | 205.00 | Effective lines of code | |
| EXEC_COMMENTS | 21.00 | Comments in executable code | |
| EXITS | 36.00 | Procedure exits | |
| FUNCTIONS | 9.00 | Number of function declarations | |
| HALSTEAD_DIFFICULTY | 74.60 | Halstead difficulty | |
| HALSTEAD_EFFORT | 0.00 | Halstead effort | |
| INTERFACE_COMPLEXITY | 54.00 | 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 | 1.00 | 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 | 5.00 | 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 | 3.00 | 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 | 0.00 | 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 | 0.00 | 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 | 1.00 | JAVA0108 Incorrect javadoc: no @param tag for 'parameter' | |
| JAVA0109 | 0.00 | JAVA0109 Incorrect javadoc: no parameter 'parameter' | |
| JAVA0110 | 2.00 | 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 | 1.00 | 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 | 0.00 | 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 | 2.00 | 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 | 0.00 | 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 | 0.00 | JAVA0144 Line exceeds maximum M characters | |
| JAVA0145 | 32.00 | 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 | 0.00 | JAVA0166 Generic exception caught | |
| JAVA0167 | 0.00 | JAVA0167 ThreadDeath not rethrown | |
| JAVA0169 | 0.00 | JAVA0169 Unnecessary catch block: exception 'exception' | |
| JAVA0170 | 0.00 | JAVA0170 Caught exception not derived from java.lang.Exception | |
| JAVA0171 | 0.00 | JAVA0171 Unused local variable | |
| JAVA0173 | 0.00 | JAVA0173 Unused method parameter | |
| JAVA0174 | 1.00 | 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 | 0.00 | JAVA0177 Variable declaration missing initializer | |
| JAVA0179 | 0.00 | 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 | 0.00 | 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 | 0.00 | 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 | 4.00 | JAVA0266 Use of System.out | |
| JAVA0267 | 0.00 | JAVA0267 Use of System.err | |
| JAVA0269 | 0.00 | JAVA0269 Contents of StringBuffer never used | |
| JAVA0270 | 0.00 | 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 | 0.00 | 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 | 526.00 | Number of lines in the source file | |
| LINE_COMMENT | 64.00 | Number of line comments | |
| LOC | 283.00 | Lines of code | |
| LOGICAL_LINES | 82.00 | Number of statements | |
| LOOPS | 2.00 | Number of loops | |
| NEST_DEPTH | 8.00 | Maximum nesting depth | |
| OPERANDS | 506.00 | Number of operands | |
| OPERATORS | 874.00 | Number of operators | |
| PARAMS | 15.00 | Number of formal parameter declarations | |
| PROGRAM_LENGTH | 1380.00 | Halstead program length | |
| PROGRAM_VOCAB | 202.00 | Halstead program vocabulary | |
| PROGRAM_VOLUME | 0.00 | Halstead program volume | |
| RETURNS | 39.00 | Number of return points from functions | |
| SIZE | 19544.00 | Size of the file in bytes | |
| UNIQUE_OPERANDS | 156.00 | Number of unique operands | |
| UNIQUE_OPERATORS | 46.00 | Number of unique operators | |
| WHITESPACE | 68.00 | Number of whitespace lines | |