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1
16 package org.apache.cocoon.acting;
17
18 import org.apache.avalon.excalibur.datasource.DataSourceComponent;
19 import org.apache.avalon.framework.configuration.Configuration;
20 import org.apache.avalon.framework.configuration.ConfigurationException;
21 import org.apache.avalon.framework.parameters.Parameters;
22 import org.apache.avalon.framework.thread.ThreadSafe;
23 import org.apache.cocoon.Constants;
24 import org.apache.cocoon.ProcessingException;
25 import org.apache.cocoon.environment.ObjectModelHelper;
26 import org.apache.cocoon.environment.Redirector;
27 import org.apache.cocoon.environment.Request;
28 import org.apache.cocoon.environment.SourceResolver;
29 import org.apache.commons.lang.StringUtils;
30
31 import java.sql.Connection  ;
32 import java.sql.PreparedStatement ;
33 import java.sql.ResultSet ;
34 import java.sql.SQLException ;
35 import java.util.HashMap ;
36 import java.util.Map ;
37
38
47 public class DatabaseSelectAction extends AbstractDatabaseAction implements ThreadSafe {
48
49 private static final Map selectStatements = new HashMap ();
50
51
56 public Map act(Redirector redirector, SourceResolver resolver, Map objectModel, String source, Parameters param) throws Exception {
57 DataSourceComponent datasource = null;
58 Connection conn = null;
59 int currentIndex = 0;
60
61 boolean reloadable = Constants.DESCRIPTOR_RELOADABLE_DEFAULT;
63 if (this.settings.containsKey("reloadable"))
64 reloadable = Boolean.valueOf((String ) this.settings.get("reloadable")).booleanValue();
65 try {
67 Configuration conf =
68 this.getConfiguration(param.getParameter("descriptor", (String ) this.settings.get("descriptor")),
69 resolver,
70 param.getParameterAsBoolean("reloadable",reloadable));
71
72 Request request = ObjectModelHelper.getRequest(objectModel);
73
74 Configuration[] keys = conf.getChild("table").getChild("keys").getChildren("key");
75 Configuration[] values = conf.getChild("table").getChild("values").getChildren("value");
76
77 PreparedStatement statement = null;
78 ResultSet rset = null;
79 boolean result = false;
80
81 for (int i = 0; i < keys.length; i++) {
82 final String parameter = keys[i].getAttribute("param");
83 Object value = request.getParameter(parameter);
84 if (StringUtils.isEmpty((String )value)) {
85 if (statement == null) {
86 final String query = this.getSelectQuery(conf);
87 datasource = this.getDataSource(conf);
88 conn = datasource.getConnection();
89 statement = conn.prepareStatement(query);
90 currentIndex = 1;
91 for (int j = 0; j < keys.length; j++, currentIndex++) {
92 this.setColumn(statement, currentIndex, request, keys[j]);
93 }
94 rset = statement.executeQuery();
95 result = rset.next();
96 }
97 if (result) {
98 value = this.getColumn(rset, request, keys[i]);
99 }
100 }
101 if (value != null) {
102 request.setAttribute(parameter, value.toString());
103 }
104 }
105
106 for (int i = 0; i < values.length; i++) {
107 final String parameter = values[i].getAttribute("param");
108 Object value = request.getParameter(parameter);
109 if (StringUtils.isEmpty((String )value)) {
110 if (statement == null) {
111 final String query = this.getSelectQuery(conf);
112 datasource = this.getDataSource(conf);
113 conn = datasource.getConnection();
114 statement = conn.prepareStatement(query);
115 currentIndex = 1;
116 for (int j = 0; j < keys.length; j++, currentIndex++) {
117 this.setColumn(statement, currentIndex, request, keys[j]);
118 }
119 rset = statement.executeQuery();
120 result = rset.next();
121 }
122 if (result) {
123 value = this.getColumn(rset, request, values[i]);
124 }
125 }
126 if (value != null) {
127 request.setAttribute(parameter, value.toString());
128 }
129 }
130 if(statement != null) {
131 statement.close();
132 }
133 return EMPTY_MAP;
134 } catch (Exception e) {
135 throw new ProcessingException("Could not prepare statement :position = " + currentIndex, e);
136 } finally {
137 if (conn != null) {
138 try {
139 conn.close();
140 } catch (SQLException sqe) {
141 getLogger().warn("There was an error closing the datasource", sqe);
142 }
143 }
144 if (datasource != null) {
145 this.dbselector.release(datasource);
146 }
147 }
148
149 }
151
152
157 protected String getSelectQuery(Configuration conf) throws ConfigurationException {
158 String query = null;
159
160 synchronized (DatabaseSelectAction.selectStatements) {
161 query = (String )DatabaseSelectAction.selectStatements.get(conf);
162
163 if (query == null) {
164 Configuration table = conf.getChild("table");
165 Configuration[] keys = table.getChild("keys").getChildren("key");
166 Configuration[] values = table.getChild("values").getChildren("value");
167
168 StringBuffer queryBuffer = new StringBuffer ("SELECT ");
169 queryBuffer.append(buildList(keys, 0));
170 queryBuffer.append(buildList(values, keys.length));
171 queryBuffer.append(" FROM ");
172 queryBuffer.append(table.getAttribute("name"));
173
174 queryBuffer.append(" WHERE ");
175 queryBuffer.append(buildList(keys, " AND "));
176 query = queryBuffer.toString();
177
178 DatabaseSelectAction.selectStatements.put(conf, query);
179 }
180 }
181 return query;
182 }
183 } |
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