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1
29
30 package com.caucho.jstl.el;
31
32 import com.caucho.el.Expr;
33 import com.caucho.log.Log;
34 import com.caucho.util.L10N;
35
36 import javax.el.ELContext;
37 import javax.servlet.jsp.JspException  ;
38 import javax.servlet.jsp.JspTagException ;
39 import javax.servlet.jsp.tagext.TagSupport ;
40 import javax.servlet.jsp.tagext.TryCatchFinally ;
41 import javax.sql.DataSource ;
42 import java.sql.Connection ;
43 import java.sql.SQLException ;
44 import java.util.logging.Level ;
45 import java.util.logging.Logger ;
46
47 public class SqlTransactionTag extends TagSupport implements TryCatchFinally {
48 private static final Logger log = Log.open(SqlTransactionTag.class);
49 private static final L10N L = new L10N(SqlTransactionTag.class);
50
51 private Expr _dataSource;
52 private Expr _isolation;
53
54 private Connection _conn;
55 private int _oldIsolation;
56
57
60 public void setDataSource(Expr dataSource)
61 {
62 _dataSource = dataSource;
63 }
64
65
68 public void setIsolation(Expr isolation)
69 {
70 _isolation = isolation;
71 }
72
73 public int doStartTag() throws JspException
74 {
75 if (pageContext.getAttribute("caucho.jstl.sql.conn") != null)
76 throw new JspTagException (L.l("nexted sql:transaction are forbidden"));
77
78 ELContext env = pageContext.getELContext();
79
80 try {
81 DataSource ds;
82
83 if (_dataSource != null)
84 ds = SqlQueryTag.getDataSource(pageContext, _dataSource.evalObject(env));
85 else
86 ds = SqlQueryTag.getDataSource(pageContext, null);
87
88 int isolationCode = -1;
89 if (_isolation != null) {
90 String isolation = _isolation.evalString(env);
91
92 if (isolation.equals("read_committed"))
93 isolationCode = Connection.TRANSACTION_READ_COMMITTED;
94 else if (isolation.equals("read_uncommitted"))
95 isolationCode = Connection.TRANSACTION_READ_UNCOMMITTED;
96 else if (isolation.equals("repeatable_read"))
97 isolationCode = Connection.TRANSACTION_REPEATABLE_READ;
98 else if (isolation.equals("serializable"))
99 isolationCode = Connection.TRANSACTION_SERIALIZABLE;
100 else
101 throw new JspTagException (L.l("unknown sql:transaction isolation ~{0}'", isolation));
102 }
103
104 _conn = ds.getConnection();
105
106 _oldIsolation = _conn.getTransactionIsolation();
107
108 _conn.setAutoCommit(false);
109
110 if (_isolation != null && isolationCode != _oldIsolation)
111 _conn.setTransactionIsolation(isolationCode);
112
113 pageContext.setAttribute("caucho.jstl.sql.conn", _conn);
114 } catch (JspException e) {
115 throw e;
116 } catch (Exception e) {
117 throw new JspException (e);
118 }
119
120 return EVAL_PAGE;
121 }
122
123 public void doCatch(Throwable t) throws Throwable
124 {
125 if (_conn != null)
126 _conn.rollback();
127
128 throw t;
129 }
130
131 public void doFinally()
132 {
133 try {
134 pageContext.removeAttribute("caucho.jstl.sql.conn");
135
136 if (_conn != null) {
137 Connection conn = _conn;
138 _conn = null;
139
140 try {
141 conn.commit();
142 } finally {
143 try {
144 conn.setTransactionIsolation(_oldIsolation);
145 } catch (SQLException e) {
146 }
147
148 try {
149 conn.close();
150 } catch (SQLException e) {
151 }
152 }
153 }
154 } catch (Exception e) {
155 log.log(Level.FINE, e.toString(), e);
156 }
157 }
158 }
159 |
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