-
Notifications
You must be signed in to change notification settings - Fork 5
/
Copy patherror_handling_lang_java.html
123 lines (123 loc) · 9.16 KB
/
error_handling_lang_java.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
<meta http-equiv="X-UA-Compatible" content="IE=9"/>
<title>WiredTiger: Error handling in Java</title>
<link href="tabs.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript" src="dynsections.js"></script>
<link href="navtree.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="resize.js"></script>
<script type="text/javascript" src="navtreedata.js"></script>
<script type="text/javascript" src="navtree.js"></script>
<script type="text/javascript">
$(document).ready(initResizable);
$(window).load(resizeHeight);
</script>
<link href="doxygen.css" rel="stylesheet" type="text/css" />
<link href="wiredtiger.css" rel="stylesheet" type="text/css"/>
</head>
<body>
<div id="top"><!-- do not remove this div, it is closed by doxygen! -->
<div id="titlearea">
<table cellspacing="0" cellpadding="0">
<tbody>
<tr style="height: 56px;">
<td id="projectlogo"><a href="http://wiredtiger.com/"><img alt="Logo" src="LogoFinal-header.png" alt="WiredTiger" /></a></td>
<td style="padding-left: 0.5em;">
<div id="projectname">
 <span id="projectnumber">Version 2.9.2</span>
</div>
<div id="projectbrief"><!-- 2.9.2 --></div>
</td>
</tr>
</tbody>
</table>
</div>
<div class="banner">
<a href="https://github.com/wiredtiger/wiredtiger">Fork me on GitHub</a>
<a class="last" href="http://groups.google.com/group/wiredtiger-users">Join my user group</a>
</div>
<!-- end header part -->
<!-- Generated by Doxygen 1.8.10 -->
<div id="navrow1" class="tabs">
<ul class="tablist">
<li><a href="index.html"><span>Main Page</span></a></li>
<li class="current"><a href="pages.html"><span>Related Pages</span></a></li>
<li><a href="modules.html"><span>Modules</span></a></li>
<li><a href="examples.html"><span>Examples</span></a></li>
<li><a href="community.html"><span>Community</span></a></li>
<li><a href="license.html"><span>License</span></a></li>
</ul>
</div>
</div><!-- top -->
<div id="side-nav" class="ui-resizable side-nav-resizable">
<div id="nav-tree">
<div id="nav-tree-contents">
<div id="nav-sync" class="sync"></div>
</div>
</div>
<div id="splitbar" style="-moz-user-select:none;"
class="ui-resizable-handle">
</div>
</div>
<script type="text/javascript">
$(document).ready(function(){initNavTree('error_handling_lang_java.html','');});
</script>
<div id="doc-content">
<div class="header">
<div class="headertitle">
<div class="title">Error handling in Java </div> </div>
</div><!--header-->
<div class="contents">
<div class="textblock"><p>WiredTiger operations return a value of 0 on success and a non-zero value on error. Error codes may be either positive or negative: positive error codes are standard error codes as described for POSIX-like systems (for example, EINVAL or EBUSY), negative error codes are WiredTiger-specific (for example, WT_ROLLBACK).</p>
<p>WiredTiger-specific error codes always appear in the -31,800 to -31,999 range.</p>
<p>Informational return values, like <code>wiredtiger.WT_NOTFOUND</code> or <code>wiredtiger.WT_DUPLICATE_KEY</code> or 0 (success), are directly returned by APIs. More severe errors are thrown as <code>WiredTigerException</code>, which may be caught by the application.</p>
<p>The <code>WiredTigerRollbackException</code> is a specific type of <code>WiredTigerException</code>, it is thrown when there is a conflict between concurrent operations. An application that catches this exception should call rollback() on the relevant transaction, and retry as necessary.</p>
<p>The <code>WiredTigerPanicException</code> is a specific type of <code>WiredTigerException</code>, it is thrown when there is an underlying problem that requires the application to exit and restart.</p>
<p>The following is a complete list of possible WiredTiger-specific return values, all constants defined in the <a class="el" href="classcom_1_1wiredtiger_1_1db_1_1wiredtiger.html">com.wiredtiger.db.wiredtiger</a> class:</p>
<dl class="section user"><dt>WT_ROLLBACK</dt><dd>This error is generated when an operation cannot be completed due to a conflict with concurrent operations. The operation may be retried; if a transaction is in progress, it should be rolled back and the operation retried in a new transaction.</dd></dl>
<dl class="section user"><dt>WT_DUPLICATE_KEY</dt><dd>This error is generated when the application attempts to insert a record with the same key as an existing record without the 'overwrite' configuration to Session.open_cursor.</dd></dl>
<dl class="section user"><dt>WT_ERROR</dt><dd>This error is returned when an error is not covered by a specific error return.</dd></dl>
<dl class="section user"><dt>WT_NOTFOUND</dt><dd>This error indicates an operation did not find a value to return. This includes cursor search and other operations where no record matched the cursor's search key such as Cursor.update or Cursor.remove.</dd></dl>
<dl class="section user"><dt>WT_PANIC</dt><dd>This error indicates an underlying problem that requires the application exit and restart. The application can exit immediately when <code>WT_PANIC</code> is returned from a WiredTiger interface, no further WiredTiger calls are required.</dd></dl>
<dl class="section user"><dt>WT_RUN_RECOVERY</dt><dd>This error is generated when wiredtiger_open is configured to return an error if recovery is required to use the database.</dd></dl>
<dl class="section user"><dt>WT_CACHE_FULL</dt><dd>This error is only generated when wiredtiger_open is configured to run in-memory, and an insert or update operation requires more than the configured cache size to complete. The operation may be retried; if a transaction is in progress, it should be rolled back and the operation retried in a new transaction.</dd></dl>
<h1><a class="anchor" id="error_translation_lang_java"></a>
Translating errors</h1>
<p>The Session.strerror and <a class="el" href="group__wt.html#gae8bf720ddb4a7a7390b70424594c40fd" title="Return information about a WiredTiger error as a string (see WT_SESSION::strerror for a thread-safe A...">wiredtiger_strerror</a> functions return the standard text message associated with any WiredTiger, ISO C, or POSIX standard API.</p>
<div class="fragment"><div class="line"> <span class="keywordflow">try</span> {</div>
<div class="line"> String key = <span class="stringliteral">"non-existent key"</span>;</div>
<div class="line"> cursor.putKeyString(key);</div>
<div class="line"> <span class="keywordflow">if</span> ((ret = cursor.remove()) != 0) {</div>
<div class="line"> System.err.println(</div>
<div class="line"> <span class="stringliteral">"cursor.remove: "</span> + wiredtiger.wiredtiger_strerror(ret));</div>
<div class="line"> <span class="keywordflow">return</span> (ret);</div>
<div class="line"> }</div>
<div class="line"> } <span class="keywordflow">catch</span> (WiredTigerException wte) { <span class="comment">/* Catch severe errors. */</span></div>
<div class="line"> System.err.println(<span class="stringliteral">"cursor.remove exception: "</span> + wte);</div>
<div class="line"> }</div>
</div><!-- fragment --> <div class="fragment"><div class="line"> <span class="keywordflow">try</span> {</div>
<div class="line"> String key = <span class="stringliteral">"non-existent key"</span>;</div>
<div class="line"> cursor.putKeyString(key);</div>
<div class="line"> <span class="keywordflow">if</span> ((ret = cursor.remove()) != 0) {</div>
<div class="line"> System.err.println(</div>
<div class="line"> <span class="stringliteral">"cursor.remove: "</span> + wiredtiger.wiredtiger_strerror(ret));</div>
<div class="line"> <span class="keywordflow">return</span> (ret);</div>
<div class="line"> }</div>
<div class="line"> } <span class="keywordflow">catch</span> (WiredTigerException wte) { <span class="comment">/* Catch severe errors. */</span></div>
<div class="line"> System.err.println(<span class="stringliteral">"cursor.remove exception: "</span> + wte);</div>
<div class="line"> }</div>
</div><!-- fragment --><p> Note that <a class="el" href="group__wt.html#gae8bf720ddb4a7a7390b70424594c40fd" title="Return information about a WiredTiger error as a string (see WT_SESSION::strerror for a thread-safe A...">wiredtiger_strerror</a> is not thread-safe. </p>
</div></div><!-- contents -->
</div><!-- doc-content -->
<!-- start footer part -->
<div id="nav-path" class="navpath"><!-- id is needed for treeview function! -->
<ul>
<li class="navelem"><a class="el" href="index.html">Reference Guide</a></li><li class="navelem"><a class="el" href="programming_lang_java.html">Writing WiredTiger applications in Java</a></li>
<li class="footer">Copyright (c) 2008-2016 MongoDB, Inc. All rights reserved. Contact <a href="mailto:[email protected]">[email protected]</a> for more information.</li>
</ul>
</div>
</body>
</html>