com.epam.deltix.util.io.RandomAccessFileStore Maven / Gradle / Ivy

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/*
 * Copyright 2021 EPAM Systems, Inc
 *
 * See the NOTICE file distributed with this work for additional information
 * regarding copyright ownership. 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 com.epam.deltix.util.io;

import java.io.*;

/**
 *
 */
public class RandomAccessFileStore implements AbstractDataStore {
    protected final File                file;
    protected RandomAccessFile          raf;
    protected boolean                   useLock = true;
    private boolean                     mIsReadOnly;
    private boolean                     mIsOpen;
    private long                        mMinSize = 0;
    private FileLockSynchronizer.Lock   lock = null;

    public RandomAccessFileStore (File f) {
        file = f;
    }

    public String           getId () {
        return (file.getPath ());
    }
        
    protected void          force (boolean metaData)
        throws IOException, InterruptedException
    {
        IOUtil.force (raf.getChannel (), metaData);
    }
    
    private void            setMinimumSizeNOW () throws IOException {
        if (mMinSize > 0 && mMinSize > raf.length ())
            raf.setLength (mMinSize);
    }
    
    public void             setMinimumSize (long size) {
        mMinSize = size;
        
        if (isOpen ()) {
            try {
                setMinimumSizeNOW ();
            } catch (IOException iox) {
                throw new com.epam.deltix.util.io.UncheckedIOException(iox);
            }            
        }
    }
    
    private void            openFile () {
        try {
            raf = new RandomAccessFile (file, mIsReadOnly ? "r" : "rw");
            
            if (useLock) 
                lock = FileLockSynchronizer.acquire (file, raf, mIsReadOnly);
            
            setMinimumSizeNOW ();
        } catch (IOException iox) {
            throw new com.epam.deltix.util.io.UncheckedIOException(iox);
        }
    }
    
    public void             open (boolean readOnly) {
        mIsReadOnly = readOnly;        
        openFile ();
        mIsOpen = true;
    }

    public boolean          isReadOnly () {
        return (mIsReadOnly);
    }

    public boolean          checkFileOpen () {
        assert raf.getChannel ().isOpen () : 
            "The file under " + this + " is closed";
        
        return (true);
    }
    
    public void             reopen () {
        assert mIsOpen : this + " is closed";
        
        if (!raf.getChannel ().isOpen()) {
            releaseLock();
            openFile ();
        }
    }
    
    public boolean          isOpen () {
        return (mIsOpen);
    }

    public void             format () {
        mIsReadOnly = false;        
        openFile ();
        mIsOpen = true;  
    }

    public void             delete () {
        close ();
        
        IOUtil.deleteUnchecked (file);
    }

    public void             close () {
        mIsOpen = false;
        
        if (raf != null) {
            try {
                releaseLock();
                raf.close ();
            } catch (IOException iox) {
                throw new com.epam.deltix.util.io.UncheckedIOException(iox);
            }
            
            raf = null;
        }
    }

    private void            releaseLock() {
        if (lock != null) {
            try {
                FileLockSynchronizer.release (lock);                
                lock = null;
            }
            catch (IOException iox) {
                throw new com.epam.deltix.util.io.UncheckedIOException(iox);
            }
        }
    }
}