Examples with Page org.h2.mvstore.Page used on opensource projects

Example 46 with Page

use of org.h2.mvstore.Page in project h2database by h2database.

the class PageDataIndex method getPage.

/**
 * Read the given page.
 *
 * @param id the page id
 * @param parent the parent, or -1 if unknown
 * @return the page
 */
PageData getPage(int id, int parent) {
    Page pd = store.getPage(id);
    if (pd == null) {
        PageDataLeaf empty = PageDataLeaf.create(this, id, parent);
        // could have been created before, but never committed
        store.logUndo(empty, null);
        store.update(empty);
        return empty;
    } else if (!(pd instanceof PageData)) {
        throw DbException.get(ErrorCode.FILE_CORRUPTED_1, "" + pd);
    }
    PageData p = (PageData) pd;
    if (parent != -1) {
        if (p.getParentPageId() != parent) {
            throw DbException.throwInternalError(p + " parent " + p.getParentPageId() + " expected " + parent);
        }
    }
    return p;
}

Example 47 with Page

use of org.h2.mvstore.Page in project h2database by h2database.

the class PageDataLeaf method getRowAt.

/**
 * Get the row at the given index.
 *
 * @param at the index
 * @return the row
 */
Row getRowAt(int at) {
    Row r = rows[at];
    if (r == null) {
        if (firstOverflowPageId == 0) {
            r = readRow(data, offsets[at], columnCount);
        } else {
            if (rowRef != null) {
                r = rowRef.get();
                if (r != null) {
                    return r;
                }
            }
            PageStore store = index.getPageStore();
            Data buff = store.createData();
            int pageSize = store.getPageSize();
            int offset = offsets[at];
            buff.write(data.getBytes(), offset, pageSize - offset);
            int next = firstOverflowPageId;
            do {
                PageDataOverflow page = index.getPageOverflow(next);
                next = page.readInto(buff);
            } while (next != 0);
            overflowRowSize = pageSize + buff.length();
            r = readRow(buff, 0, columnCount);
        }
        r.setKey(keys[at]);
        if (firstOverflowPageId != 0) {
            rowRef = new SoftReference<>(r);
        } else {
            rows[at] = r;
            memoryChange(true, r);
        }
    }
    return r;
}

Example 48 with Page

use of org.h2.mvstore.Page in project h2database by h2database.

the class PageDataLeaf method addRowTry.

@Override
int addRowTry(Row row) {
    index.getPageStore().logUndo(this, data);
    int rowLength = getRowLength(row);
    int pageSize = index.getPageStore().getPageSize();
    int last = entryCount == 0 ? pageSize : offsets[entryCount - 1];
    int keyOffsetPairLen = 2 + Data.getVarLongLen(row.getKey());
    if (entryCount > 0 && last - rowLength < start + keyOffsetPairLen) {
        int x = findInsertionPoint(row.getKey());
        if (entryCount > 1) {
            if (entryCount < 5) {
                // required, otherwise the index doesn't work correctly
                return entryCount / 2;
            }
            if (index.isSortedInsertMode()) {
                return x < 2 ? 1 : x > entryCount - 1 ? entryCount - 1 : x;
            }
            // split near the insertion point to better fill pages
            // split in half would be:
            // return entryCount / 2;
            int third = entryCount / 3;
            return x < third ? third : x >= 2 * third ? 2 * third : x;
        }
        return x;
    }
    index.getPageStore().logUndo(this, data);
    int x;
    if (entryCount == 0) {
        x = 0;
    } else {
        if (!optimizeUpdate) {
            readAllRows();
        }
        x = findInsertionPoint(row.getKey());
    }
    written = false;
    changeCount = index.getPageStore().getChangeCount();
    last = x == 0 ? pageSize : offsets[x - 1];
    int offset = last - rowLength;
    start += keyOffsetPairLen;
    offsets = insert(offsets, entryCount, x, offset);
    add(offsets, x + 1, entryCount + 1, -rowLength);
    keys = insert(keys, entryCount, x, row.getKey());
    rows = insert(rows, entryCount, x, row);
    entryCount++;
    index.getPageStore().update(this);
    if (optimizeUpdate) {
        if (writtenData && offset >= start) {
            byte[] d = data.getBytes();
            int dataStart = offsets[entryCount - 1] + rowLength;
            int dataEnd = offsets[x];
            System.arraycopy(d, dataStart, d, dataStart - rowLength, dataEnd - dataStart + rowLength);
            data.setPos(dataEnd);
            for (int j = 0; j < columnCount; j++) {
                data.writeValue(row.getValue(j));
            }
        }
    }
    if (offset < start) {
        writtenData = false;
        if (entryCount > 1) {
            DbException.throwInternalError("" + entryCount);
        }
        // need to write the overflow page id
        start += 4;
        int remaining = rowLength - (pageSize - start);
        // fix offset
        offset = start;
        offsets[x] = offset;
        int previous = getPos();
        int dataOffset = pageSize;
        int page = index.getPageStore().allocatePage();
        firstOverflowPageId = page;
        this.overflowRowSize = pageSize + rowLength;
        writeData();
        // free up the space used by the row
        Row r = rows[0];
        rowRef = new SoftReference<>(r);
        rows[0] = null;
        Data all = index.getPageStore().createData();
        all.checkCapacity(data.length());
        all.write(data.getBytes(), 0, data.length());
        data.truncate(index.getPageStore().getPageSize());
        do {
            int type, size, next;
            if (remaining <= pageSize - PageDataOverflow.START_LAST) {
                type = Page.TYPE_DATA_OVERFLOW | Page.FLAG_LAST;
                size = remaining;
                next = 0;
            } else {
                type = Page.TYPE_DATA_OVERFLOW;
                size = pageSize - PageDataOverflow.START_MORE;
                next = index.getPageStore().allocatePage();
            }
            PageDataOverflow overflow = PageDataOverflow.create(index.getPageStore(), page, type, previous, next, all, dataOffset, size);
            index.getPageStore().update(overflow);
            dataOffset += size;
            remaining -= size;
            previous = page;
            page = next;
        } while (remaining > 0);
    }
    if (rowRef == null) {
        memoryChange(true, row);
    } else {
        memoryChange(true, null);
    }
    return -1;
}

Example 49 with Page

use of org.h2.mvstore.Page in project h2database by h2database.

the class PageDataOverflow method moveTo.

@Override
public void moveTo(Session session, int newPos) {
    // load the pages into the cache, to ensure old pages
    // are written
    Page parent = store.getPage(parentPageId);
    if (parent == null) {
        throw DbException.throwInternalError();
    }
    PageDataOverflow next = null;
    if (nextPage != 0) {
        next = (PageDataOverflow) store.getPage(nextPage);
    }
    store.logUndo(this, data);
    PageDataOverflow p2 = PageDataOverflow.create(store, newPos, type, parentPageId, nextPage, data, start, size);
    store.update(p2);
    if (next != null) {
        next.setParentPageId(newPos);
        store.update(next);
    }
    if (parent instanceof PageDataOverflow) {
        PageDataOverflow p1 = (PageDataOverflow) parent;
        p1.setNext(getPos(), newPos);
    } else {
        PageDataLeaf p1 = (PageDataLeaf) parent;
        p1.setOverflow(getPos(), newPos);
    }
    store.update(parent);
    store.free(getPos());
}

Example 50 with Page

use of org.h2.mvstore.Page in project h2database by h2database.

the class Server method openBrowser.

/**
 * Open a new browser tab or window with the given URL.
 *
 * @param url the URL to open
 */
public static void openBrowser(String url) throws Exception {
    try {
        String osName = StringUtils.toLowerEnglish(Utils.getProperty("os.name", "linux"));
        Runtime rt = Runtime.getRuntime();
        String browser = Utils.getProperty(SysProperties.H2_BROWSER, null);
        if (browser == null) {
            // under Linux, this will point to the default system browser
            try {
                browser = System.getenv("BROWSER");
            } catch (SecurityException se) {
            // ignore
            }
        }
        if (browser != null) {
            if (browser.startsWith("call:")) {
                browser = browser.substring("call:".length());
                Utils.callStaticMethod(browser, url);
            } else if (browser.contains("%url")) {
                String[] args = StringUtils.arraySplit(browser, ',', false);
                for (int i = 0; i < args.length; i++) {
                    args[i] = StringUtils.replaceAll(args[i], "%url", url);
                }
                rt.exec(args);
            } else if (osName.contains("windows")) {
                rt.exec(new String[] { "cmd.exe", "/C", browser, url });
            } else {
                rt.exec(new String[] { browser, url });
            }
            return;
        }
        try {
            Class<?> desktopClass = Class.forName("java.awt.Desktop");
            // Desktop.isDesktopSupported()
            Boolean supported = (Boolean) desktopClass.getMethod("isDesktopSupported").invoke(null, new Object[0]);
            URI uri = new URI(url);
            if (supported) {
                // Desktop.getDesktop();
                Object desktop = desktopClass.getMethod("getDesktop").invoke(null);
                // desktop.browse(uri);
                desktopClass.getMethod("browse", URI.class).invoke(desktop, uri);
                return;
            }
        } catch (Exception e) {
        // ignore
        }
        if (osName.contains("windows")) {
            rt.exec(new String[] { "rundll32", "url.dll,FileProtocolHandler", url });
        } else if (osName.contains("mac") || osName.contains("darwin")) {
            // Mac OS: to open a page with Safari, use "open -a Safari"
            Runtime.getRuntime().exec(new String[] { "open", url });
        } else {
            String[] browsers = { "xdg-open", "chromium", "google-chrome", "firefox", "mozilla-firefox", "mozilla", "konqueror", "netscape", "opera", "midori" };
            boolean ok = false;
            for (String b : browsers) {
                try {
                    rt.exec(new String[] { b, url });
                    ok = true;
                    break;
                } catch (Exception e) {
                // ignore and try the next
                }
            }
            if (!ok) {
                // No success in detection.
                throw new Exception("Browser detection failed and system property " + SysProperties.H2_BROWSER + " not set");
            }
        }
    } catch (Exception e) {
        throw new Exception("Failed to start a browser to open the URL " + url + ": " + e.getMessage());
    }
}