org.h2.mvstore.MVStoreTool Maven / Gradle / Ivy
/*
* Copyright 2004-2013 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.mvstore;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.Writer;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import org.h2.mvstore.type.StringDataType;
import org.h2.store.fs.FilePath;
/**
* Utility methods used in combination with the MVStore.
*/
public class MVStoreTool {
/**
* Runs this tool.
* Options are case sensitive. Supported options are:
*
* [-dump <dir>]
* Dump the contends of the file
*
* @param args the command line arguments
*/
public static void main(String... args) {
for (int i = 0; i < args.length; i++) {
if ("-dump".equals(args[i])) {
String fileName = args[++i];
dump(fileName, new PrintWriter(System.out));
}
}
}
/**
* Read the contents of the file and write them to system out.
*
* @param fileName the name of the file
*/
public static void dump(String fileName) {
dump(fileName, new PrintWriter(System.out));
}
/**
* Read the contents of the file and display them in a human-readable
* format.
*
* @param fileName the name of the file
* @param writer the print writer
*/
public static void dump(String fileName, Writer writer) {
PrintWriter pw = new PrintWriter(writer, true);
if (!FilePath.get(fileName).exists()) {
pw.println("File not found: " + fileName);
return;
}
FileChannel file = null;
int blockSize = MVStore.BLOCK_SIZE;
try {
file = FilePath.get(fileName).open("r");
long fileSize = file.size();
int len = Long.toHexString(fileSize).length();
ByteBuffer block = ByteBuffer.allocate(4096);
for (long pos = 0; pos < fileSize;) {
block.rewind();
DataUtils.readFully(file, pos, block);
block.rewind();
int headerType = block.get();
if (headerType == 'H') {
pw.printf("%0" + len + "x fileHeader %s%n",
pos,
new String(block.array(), DataUtils.LATIN).trim());
pos += blockSize;
continue;
}
if (headerType != 'c') {
pos += blockSize;
continue;
}
block.position(0);
Chunk c = Chunk.readChunkHeader(block, pos);
int length = c.len * MVStore.BLOCK_SIZE;
pw.printf("%n%0" + len + "x chunkHeader %s%n",
pos, c.toString());
ByteBuffer chunk = ByteBuffer.allocate(length);
DataUtils.readFully(file, pos, chunk);
int p = block.position();
pos += length;
int remaining = c.pageCount;
while (remaining > 0) {
chunk.position(p);
int pageSize = chunk.getInt();
// check value (ignored)
chunk.getShort();
int mapId = DataUtils.readVarInt(chunk);
int entries = DataUtils.readVarInt(chunk);
int type = chunk.get();
boolean compressed = (type & 2) != 0;
boolean node = (type & 1) != 0;
pw.printf(
"+%0" + len +
"x %s, map %x, %d entries, %d bytes%n",
p,
(node ? "node" : "leaf") +
(compressed ? " compressed" : ""),
mapId,
node ? entries + 1 : entries,
pageSize);
p += pageSize;
remaining--;
long[] children = null;
long[] counts = null;
if (node) {
children = new long[entries + 1];
for (int i = 0; i <= entries; i++) {
children[i] = chunk.getLong();
}
counts = new long[entries + 1];
for (int i = 0; i <= entries; i++) {
long s = DataUtils.readVarLong(chunk);
counts[i] = s;
}
}
String[] keys = new String[entries];
if (mapId == 0) {
if (!compressed) {
for (int i = 0; i < entries; i++) {
String k = StringDataType.INSTANCE.read(chunk);
keys[i] = k;
}
}
if (node) {
// meta map node
for (int i = 0; i < entries; i++) {
long cp = children[i];
pw.printf(" %d children < %s @ " +
"chunk %x +%0" +
len + "x%n",
counts[i],
keys[i],
DataUtils.getPageChunkId(cp),
DataUtils.getPageOffset(cp));
}
long cp = children[entries];
pw.printf(" %d children >= %s @ chunk %x +%0" +
len + "x%n",
counts[entries],
keys[entries],
DataUtils.getPageChunkId(cp),
DataUtils.getPageOffset(cp));
} else if (!compressed) {
// meta map leaf
String[] values = new String[entries];
for (int i = 0; i < entries; i++) {
String v = StringDataType.INSTANCE.read(chunk);
values[i] = v;
}
for (int i = 0; i < entries; i++) {
pw.println(" " + keys[i] +
" = " + values[i]);
}
}
} else {
if (node) {
for (int i = 0; i <= entries; i++) {
long cp = children[i];
pw.printf(" %d children @ chunk %x +%0" +
len + "x%n",
counts[i],
DataUtils.getPageChunkId(cp),
DataUtils.getPageOffset(cp));
}
}
}
}
int footerPos = chunk.limit() - Chunk.FOOTER_LENGTH;
chunk.position(footerPos);
pw.printf(
"+%0" + len + "x chunkFooter %s%n",
footerPos,
new String(chunk.array(), chunk.position(),
Chunk.FOOTER_LENGTH, DataUtils.LATIN).trim());
}
pw.printf("%n%0" + len + "x eof%n", fileSize);
} catch (IOException e) {
pw.println("ERROR: " + e);
e.printStackTrace(pw);
} finally {
if (file != null) {
try {
file.close();
} catch (IOException e) {
// ignore
}
}
}
pw.flush();
}
}
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