X-Git-Url: https://code.wpia.club/?a=blobdiff_plain;f=src%2Forg%2Fcacert%2Fgigi%2Fdatabase%2FDatabaseConnection.java;h=c85b5348d6e253c2dd96d1219723b9913751db23;hb=bd738ff4450f7fabe08c4ca5bd3f7597d0b011ef;hp=67364d0a06fe95ee02760d5c270e8121a6c25e9b;hpb=8552a0eaf52ad7a05cb045ee9423cfc8a45c336a;p=gigi.git

diff --git a/src/org/cacert/gigi/database/DatabaseConnection.java b/src/org/cacert/gigi/database/DatabaseConnection.java
index 67364d0a..c85b5348 100644
--- a/src/org/cacert/gigi/database/DatabaseConnection.java
+++ b/src/org/cacert/gigi/database/DatabaseConnection.java
@@ -2,12 +2,16 @@ package org.cacert.gigi.database;
 
 import java.io.IOException;
 import java.io.InputStream;
+import java.io.PrintWriter;
 import java.sql.Connection;
 import java.sql.DriverManager;
+import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.sql.Statement;
 import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map.Entry;
 import java.util.Properties;
 import java.util.StringJoiner;
 import java.util.regex.Matcher;
@@ -17,13 +21,93 @@ import org.cacert.gigi.database.SQLFileManager.ImportType;
 
 public class DatabaseConnection {
 
-    public static final int CURRENT_SCHEMA_VERSION = 5;
+    public static final int MAX_CACHED_INSTANCES = 3;
+
+    private static class StatementDescriptor {
+
+        String query;
+
+        boolean scrollable;
+
+        int instance;
+
+        PreparedStatement target;
+
+        public StatementDescriptor(String query, boolean scrollable) {
+            this.query = query;
+            this.scrollable = scrollable;
+            this.instance = 0;
+        }
+
+        public synchronized void instanciate(Connection c) throws SQLException {
+            if (scrollable) {
+                target = c.prepareStatement(query, ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY);
+            } else {
+                target = c.prepareStatement(query, query.startsWith("SELECT ") ? Statement.NO_GENERATED_KEYS : Statement.RETURN_GENERATED_KEYS);
+            }
+
+        }
+
+        public synchronized PreparedStatement getTarget() {
+            return target;
+        }
+
+        public synchronized void increase() {
+            if (target != null) {
+                throw new IllegalStateException();
+            }
+            instance++;
+        }
+
+        @Override
+        public int hashCode() {
+            final int prime = 31;
+            int result = 1;
+            result = prime * result + instance;
+            result = prime * result + ((query == null) ? 0 : query.hashCode());
+            result = prime * result + (scrollable ? 1231 : 1237);
+            return result;
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (this == obj) {
+                return true;
+            }
+            if (obj == null) {
+                return false;
+            }
+            if (getClass() != obj.getClass()) {
+                return false;
+            }
+            StatementDescriptor other = (StatementDescriptor) obj;
+            if (instance != other.instance) {
+                return false;
+            }
+            if (query == null) {
+                if (other.query != null) {
+                    return false;
+                }
+            } else if ( !query.equals(other.query)) {
+                return false;
+            }
+            if (scrollable != other.scrollable) {
+                return false;
+            }
+            return true;
+        }
+
+    }
+
+    public static final int CURRENT_SCHEMA_VERSION = 9;
 
     public static final int CONNECTION_TIMEOUT = 24 * 60 * 60;
 
     private Connection c;
 
-    private HashMap<String, GigiPreparedStatement> statements = new HashMap<String, GigiPreparedStatement>();
+    private HashMap<StatementDescriptor, PreparedStatement> statements = new HashMap<StatementDescriptor, PreparedStatement>();
+
+    HashSet<PreparedStatement> underUse = new HashSet<>();
 
     private static Properties credentials;
 
@@ -48,36 +132,40 @@ public class DatabaseConnection {
         }
     }
 
-    public GigiPreparedStatement prepare(String query) {
-        ensureOpen();
-        query = preprocessQuery(query);
-        GigiPreparedStatement statement = statements.get(query);
-        if (statement == null) {
-            try {
-                statement = new GigiPreparedStatement(c.prepareStatement(query, query.startsWith("SELECT ") ? Statement.NO_GENERATED_KEYS : Statement.RETURN_GENERATED_KEYS));
-            } catch (SQLException e) {
-                throw new Error(e);
-            }
-            statements.put(query, statement);
-        }
-        return statement;
+    protected synchronized PreparedStatement prepareInternal(String query) throws SQLException {
+        return prepareInternal(query, false);
     }
 
-    public GigiPreparedStatement prepareScrollable(String query) {
+    protected synchronized PreparedStatement prepareInternal(String query, boolean scrollable) throws SQLException {
+
         ensureOpen();
         query = preprocessQuery(query);
-        GigiPreparedStatement statement = statements.get(query);
-        if (statement == null) {
-            try {
-                statement = new GigiPreparedStatement(c.prepareStatement(query, ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY));
-            } catch (SQLException e) {
-                throw new Error(e);
+        StatementDescriptor searchHead = new StatementDescriptor(query, scrollable);
+        PreparedStatement statement = null;
+        while (statement == null) {
+            statement = statements.get(searchHead);
+            if (statement == null) {
+                searchHead.instanciate(c);
+                statement = searchHead.getTarget();
+                if (searchHead.instance >= MAX_CACHED_INSTANCES) {
+                    return statement;
+                }
+                underUse.add(statement);
+                statements.put(searchHead, statement);
+            } else if (underUse.contains(statement)) {
+                searchHead.increase();
+                statement = null;
+            } else {
+                underUse.add(statement);
             }
-            statements.put(query, statement);
         }
         return statement;
     }
 
+    protected synchronized PreparedStatement prepareInternalScrollable(String query) throws SQLException {
+        return prepareInternal(query, true);
+    }
+
     private long lastAction = System.currentTimeMillis();
 
     private void ensureOpen() {
@@ -95,16 +183,13 @@ public class DatabaseConnection {
         lastAction = System.currentTimeMillis();
     }
 
-    private static ThreadLocal<DatabaseConnection> instances = new ThreadLocal<DatabaseConnection>() {
+    private static volatile DatabaseConnection instance;
 
-        @Override
-        protected DatabaseConnection initialValue() {
-            return new DatabaseConnection();
+    public static synchronized DatabaseConnection getInstance() {
+        if (instance == null) {
+            instance = new DatabaseConnection();
         }
-    };
-
-    public static DatabaseConnection getInstance() {
-        return instances.get();
+        return instance;
     }
 
     public static boolean isInited() {
@@ -116,10 +201,12 @@ public class DatabaseConnection {
             throw new Error("Re-initiaizing is forbidden.");
         }
         credentials = conf;
-        GigiResultSet rs = getInstance().prepare("SELECT version FROM \"schemeVersion\" ORDER BY version DESC LIMIT 1;").executeQuery();
         int version = 0;
-        if (rs.next()) {
-            version = rs.getInt(1);
+        try (GigiPreparedStatement gigiPreparedStatement = new GigiPreparedStatement("SELECT version FROM \"schemeVersion\" ORDER BY version DESC LIMIT 1;")) {
+            GigiResultSet rs = gigiPreparedStatement.executeQuery();
+            if (rs.next()) {
+                version = rs.getInt(1);
+            }
         }
         if (version == CURRENT_SCHEMA_VERSION) {
             return; // Good to go
@@ -130,10 +217,6 @@ public class DatabaseConnection {
         upgrade(version);
     }
 
-    public void beginTransaction() throws SQLException {
-        c.setAutoCommit(false);
-    }
-
     private static void upgrade(int version) {
         try {
             Statement s = getInstance().c.createStatement();
@@ -161,22 +244,6 @@ public class DatabaseConnection {
         }
     }
 
-    public void commitTransaction() throws SQLException {
-        c.commit();
-        c.setAutoCommit(true);
-    }
-
-    public void quitTransaction() {
-        try {
-            if ( !c.getAutoCommit()) {
-                c.rollback();
-                c.setAutoCommit(true);
-            }
-        } catch (SQLException e) {
-            e.printStackTrace();
-        }
-    }
-
     public static final String preprocessQuery(String originalQuery) {
         originalQuery = originalQuery.replace('`', '"');
         if (originalQuery.matches("^INSERT INTO [^ ]+ SET .*")) {
@@ -211,4 +278,28 @@ public class DatabaseConnection {
         }
         return ident;
     }
+
+    protected synchronized void returnStatement(PreparedStatement target) throws SQLException {
+        if ( !underUse.remove(target)) {
+            target.close();
+        }
+    }
+
+    public synchronized int getNumberOfLockedStatements() {
+        return underUse.size();
+    }
+
+    public synchronized void lockedStatements(PrintWriter writer) {
+        writer.println(underUse.size());
+        for (PreparedStatement ps : underUse) {
+            for (Entry<StatementDescriptor, PreparedStatement> e : statements.entrySet()) {
+                if (e.getValue() == ps) {
+                    writer.println("<br/>");
+                    writer.println(e.getKey().instance + ":");
+
+                    writer.println(e.getKey().query);
+                }
+            }
+        }
+    }
 }