/*
* Copyright (C) 2006 The Android Open Source Project
*
* 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.
*/
package android.database.sqlite;
import android.os.SystemClock;
/**
* A pre-compiled statement against a {@link SQLiteDatabase} that can be reused.
* The statement cannot return multiple rows, but 1x1 result sets are allowed.
* Don't use SQLiteStatement constructor directly, please use
* {@link SQLiteDatabase#compileStatement(String)}
*/
public class SQLiteStatement extends SQLiteProgram
{
/**
* Don't use SQLiteStatement constructor directly, please use
* {@link SQLiteDatabase#compileStatement(String)}
* @param db
* @param sql
*/
/* package */ SQLiteStatement(SQLiteDatabase db, String sql) {
super(db, sql);
}
/**
* Execute this SQL statement, if it is not a query. For example,
* CREATE TABLE, DELTE, INSERT, etc.
*
* @throws android.database.SQLException If the SQL string is invalid for
* some reason
*/
public void execute() {
if (!mDatabase.isOpen()) {
throw new IllegalStateException("database " + mDatabase.getPath() + " already closed");
}
long timeStart = SystemClock.uptimeMillis();
mDatabase.lock();
acquireReference();
try {
native_execute();
mDatabase.logTimeStat(mSql, timeStart);
} finally {
releaseReference();
mDatabase.unlock();
}
}
/**
* Execute this SQL statement and return the ID of the row inserted due to this call.
* The SQL statement should be an INSERT for this to be a useful call.
*
* @return the row ID of the last row inserted, if this insert is successful. -1 otherwise.
*
* @throws android.database.SQLException If the SQL string is invalid for
* some reason
*/
public long executeInsert() {
if (!mDatabase.isOpen()) {
throw new IllegalStateException("database " + mDatabase.getPath() + " already closed");
}
long timeStart = SystemClock.uptimeMillis();
mDatabase.lock();
acquireReference();
try {
native_execute();
mDatabase.logTimeStat(mSql, timeStart);
return (mDatabase.lastChangeCount() > 0) ? mDatabase.lastInsertRow() : -1;
} finally {
releaseReference();
mDatabase.unlock();
}
}
/**
* Execute a statement that returns a 1 by 1 table with a numeric value.
* For example, SELECT COUNT(*) FROM table;
*
* @return The result of the query.
*
* @throws android.database.sqlite.SQLiteDoneException if the query returns zero rows
*/
public long simpleQueryForLong() {
if (!mDatabase.isOpen()) {
throw new IllegalStateException("database " + mDatabase.getPath() + " already closed");
}
long timeStart = SystemClock.uptimeMillis();
mDatabase.lock();
acquireReference();
try {
long retValue = native_1x1_long();
mDatabase.logTimeStat(mSql, timeStart);
return retValue;
} finally {
releaseReference();
mDatabase.unlock();
}
}
/**
* Execute a statement that returns a 1 by 1 table with a text value.
* For example, SELECT COUNT(*) FROM table;
*
* @return The result of the query.
*
* @throws android.database.sqlite.SQLiteDoneException if the query returns zero rows
*/
public String simpleQueryForString() {
if (!mDatabase.isOpen()) {
throw new IllegalStateException("database " + mDatabase.getPath() + " already closed");
}
long timeStart = SystemClock.uptimeMillis();
mDatabase.lock();
acquireReference();
try {
String retValue = native_1x1_string();
mDatabase.logTimeStat(mSql, timeStart);
return retValue;
} finally {
releaseReference();
mDatabase.unlock();
}
}
private final native void native_execute();
private final native long native_1x1_long();
private final native String native_1x1_string();
}