1 files changed, 184 insertions, 0 deletions
diff --git a/dblib/common/src/main/java/org/apache/tomcat/jdbc/pool/interceptor/ConnectionState.java b/dblib/common/src/main/java/org/apache/tomcat/jdbc/pool/interceptor/ConnectionState.java
new file mode 100644
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@@ -0,0 +1,184 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * openecomp
+ * ================================================================================
+ * Copyright (C) 2016 - 2017 AT&T
+ * ================================================================================
+ * Licensed 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.
+ * ============LICENSE_END=========================================================
+ */
+
+/*
+ * 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.tomcat.jdbc.pool.interceptor;
+
+import java.lang.reflect.Method;
+import java.sql.SQLException;
+
+import org.apache.juli.logging.Log;
+import org.apache.juli.logging.LogFactory;
+import org.apache.tomcat.jdbc.pool.ConnectionPool;
+import org.apache.tomcat.jdbc.pool.DataSourceFactory;
+import org.apache.tomcat.jdbc.pool.JdbcInterceptor;
+import org.apache.tomcat.jdbc.pool.PoolConfiguration;
+import org.apache.tomcat.jdbc.pool.PooledConnection;
+
+/**
+ * Interceptor that keep track of connection state to avoid roundtrips to the database.
+ * The {@link org.apache.tomcat.jdbc.pool.ConnectionPool} is optimized to do as little work as possible.
+ * The pool itself doesn't remember settings like {@link java.sql.Connection#setAutoCommit(boolean)},
+ * {@link java.sql.Connection#setReadOnly(boolean)}, {@link java.sql.Connection#setCatalog(String)} or
+ * {@link java.sql.Connection#setTransactionIsolation(int)}. It relies on the application to remember how and when
+ * these settings have been applied.
+ * In the cases where the application code doesn't know or want to keep track of the state, this interceptor helps cache the
+ * state, and it also avoids roundtrips to the database asking for it.
+ *
+ */
+
+public class ConnectionState extends JdbcInterceptor  {
+    private static final Log log = LogFactory.getLog(ConnectionState.class);
+
+    protected final String[] readState = {"getAutoCommit","getTransactionIsolation","isReadOnly","getCatalog"};
+    protected final String[] writeState = {"setAutoCommit","setTransactionIsolation","setReadOnly","setCatalog"};
+
+    protected Boolean autoCommit = null;
+    protected Integer transactionIsolation = null;
+    protected Boolean readOnly = null;
+    protected String catalog = null;
+
+
+    @Override
+    public void reset(ConnectionPool parent, PooledConnection con) {
+        if (parent==null || con==null) {
+            //we are resetting, reset our defaults
+            autoCommit = null;
+            transactionIsolation = null;
+            readOnly = null;
+            catalog = null;
+            return;
+        }
+        PoolConfiguration poolProperties = parent.getPoolProperties();
+        if (poolProperties.getDefaultTransactionIsolation()!=DataSourceFactory.UNKNOWN_TRANSACTIONISOLATION) {
+            try {
+                if (transactionIsolation==null || transactionIsolation.intValue()!=poolProperties.getDefaultTransactionIsolation()) {
+                    con.getConnection().setTransactionIsolation(poolProperties.getDefaultTransactionIsolation());
+                    transactionIsolation = Integer.valueOf(poolProperties.getDefaultTransactionIsolation());
+                }
+            }catch (SQLException x) {
+                transactionIsolation = null;
+                log.error("Unable to reset transaction isolation state to connection.",x);
+            }
+        }
+        if (poolProperties.getDefaultReadOnly()!=null) {
+            try {
+                if (readOnly==null || readOnly.booleanValue()!=poolProperties.getDefaultReadOnly().booleanValue()) {
+                    con.getConnection().setReadOnly(poolProperties.getDefaultReadOnly().booleanValue());
+                    readOnly = poolProperties.getDefaultReadOnly();
+                }
+            }catch (SQLException x) {
+                readOnly = null;
+                log.error("Unable to reset readonly state to connection.",x);
+            }
+        }
+        if (poolProperties.getDefaultAutoCommit()!=null) {
+            try {
+                if (autoCommit==null || autoCommit.booleanValue()!=poolProperties.getDefaultAutoCommit().booleanValue()) {
+                    con.getConnection().setAutoCommit(poolProperties.getDefaultAutoCommit().booleanValue());
+                    autoCommit = poolProperties.getDefaultAutoCommit();
+                }
+            }catch (SQLException x) {
+                autoCommit = null;
+                log.error("Unable to reset autocommit state to connection.",x);
+            }
+        }
+        if (poolProperties.getDefaultCatalog()!=null) {
+            try {
+                if (catalog==null || (!catalog.equals(poolProperties.getDefaultCatalog()))) {
+                    con.getConnection().setCatalog(poolProperties.getDefaultCatalog());
+                    catalog = poolProperties.getDefaultCatalog();
+                }
+            }catch (SQLException x) {
+                catalog = null;
+                log.error("Unable to reset default catalog state to connection.",x);
+            }
+        }
+
+    }
+
+
+    @Override
+    public void disconnected(ConnectionPool parent, PooledConnection con, boolean finalizing) {
+        //we are resetting, reset our defaults
+        autoCommit = null;
+        transactionIsolation = null;
+        readOnly = null;
+        catalog = null;
+        super.disconnected(parent, con, finalizing);
+    }
+
+
+
+    @Override
+    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
+        String name = method.getName();
+        boolean read = false;
+        int index = -1;
+        for (int i=0; (!read) && i<readState.length; i++) {
+            read = compare(name,readState[i]);
+            if (read) index = i;
+        }
+        boolean write = false;
+        for (int i=0; (!write) && (!read) && i<writeState.length; i++) {
+            write = compare(name,writeState[i]);
+            if (write) index = i;
+        }
+        Object result = null;
+        if (read) {
+            switch (index) {
+                case 0:{result = autoCommit; break;}
+                case 1:{result = transactionIsolation; break;}
+                case 2:{result = readOnly; break;}
+                case 3:{result = catalog; break;}
+                default: // NOOP
+            }
+            //return cached result, if we have it
+            if (result!=null) return result;
+        }
+
+        result = super.invoke(proxy, method, args);
+        if (read || write) {
+            switch (index) {
+                case 0:{autoCommit = (Boolean) (read?result:args[0]); break;}
+                case 1:{transactionIsolation = (Integer)(read?result:args[0]); break;}
+                case 2:{readOnly = (Boolean)(read?result:args[0]); break;}
+                case 3:{catalog = (String)(read?result:args[0]); break;}
+            }
+        }
+        return result;
+    }
+
+}