Java tutorial
/******************************************************************************* * Copyright (c) 2003, 2009 IBM Corporation and others. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * Contributors: * IBM Corporation - initial API and implementation *******************************************************************************/ package com.siteview.mde.internal.ui.launcher; import java.io.*; import java.lang.reflect.InvocationTargetException; import org.eclipse.core.runtime.IProgressMonitor; import org.eclipse.jface.dialogs.*; import org.eclipse.jface.operation.IRunnableWithProgress; import com.siteview.mde.internal.ui.MDEPlugin; import com.siteview.mde.internal.ui.MDEUIMessages; import org.eclipse.swt.SWT; import org.eclipse.swt.graphics.Point; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.widgets.*; /** * Displays the error log in non-Win32 platforms - see bug 55314. */ public final class OpenLogDialog extends TrayDialog { // maximum log file size public static final long MAX_FILE_LENGTH = 1024 * 1024; // input log file private File logFile; // location/size configuration private IDialogSettings dialogSettings; private Point dialogLocation; private Point dialogSize; private int DEFAULT_WIDTH = 750; private int DEFAULT_HEIGHT = 800; public OpenLogDialog(Shell parentShell, File logFile) { super(parentShell); this.logFile = logFile; setShellStyle(SWT.DIALOG_TRIM | SWT.RESIZE | SWT.MAX | SWT.MIN | SWT.MODELESS); } /* * (non-Javadoc) Method declared on Window. */ protected void configureShell(Shell newShell) { super.configureShell(newShell); newShell.setText(MDEUIMessages.OpenLogDialog_title); readConfiguration(); } /* * (non-Javadoc) Method declared on Dialog. */ protected void createButtonsForButtonBar(Composite parent) { createButton(parent, IDialogConstants.CLOSE_ID, IDialogConstants.CLOSE_LABEL, true); } public void create() { super.create(); // dialog location if (dialogLocation != null) getShell().setLocation(dialogLocation); // dialog size if (dialogSize != null) getShell().setSize(dialogSize); else getShell().setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT); getButton(IDialogConstants.CLOSE_ID).setFocus(); } /* * (non-Javadoc) Method declared on Dialog. */ protected Control createDialogArea(Composite parent) { Composite outer = (Composite) super.createDialogArea(parent); Text text = new Text(outer, SWT.MULTI | SWT.BORDER | SWT.READ_ONLY | SWT.V_SCROLL | SWT.NO_FOCUS | SWT.H_SCROLL); text.setBackground(parent.getDisplay().getSystemColor(SWT.COLOR_LIST_BACKGROUND)); GridData gridData = new GridData(GridData.HORIZONTAL_ALIGN_FILL | GridData.VERTICAL_ALIGN_FILL); gridData.grabExcessVerticalSpace = true; gridData.grabExcessHorizontalSpace = true; text.setLayoutData(gridData); text.setText(getLogSummary()); return outer; } private String getLogSummary() { StringWriter out = new StringWriter(); PrintWriter writer = new PrintWriter(out); if (logFile.length() > MAX_FILE_LENGTH) { readLargeFileWithMonitor(writer); } else { readFileWithMonitor(writer); } writer.close(); return out.toString(); } // reading file within MAX_FILE_LENGTH size private void readFile(PrintWriter writer) throws FileNotFoundException, IOException { BufferedReader bReader = new BufferedReader(new FileReader(logFile)); while (bReader.ready()) writer.println(bReader.readLine()); } // reading large files private void readLargeFile(PrintWriter writer) throws FileNotFoundException, IOException { RandomAccessFile random = null; boolean hasStarted = false; try { random = new RandomAccessFile(logFile, "r"); //$NON-NLS-1$ random.seek(logFile.length() - MAX_FILE_LENGTH); for (;;) { String line = random.readLine(); if (line == null) break; line = line.trim(); if (line.length() == 0) continue; if (!hasStarted && (line.startsWith("!ENTRY") || line.startsWith("!SESSION"))) //$NON-NLS-1$ //$NON-NLS-2$ hasStarted = true; if (hasStarted) writer.println(line); continue; } } finally { try { if (random != null) random.close(); } catch (IOException e1) { } } } /* * (non-Javadoc) * * @see org.eclipse.jface.dialogs.Dialog#buttonPressed(int) */ protected void buttonPressed(int buttonId) { if (buttonId == IDialogConstants.CLOSE_ID) { storeSettings(); close(); } super.buttonPressed(buttonId); } private void readLargeFileWithMonitor(final PrintWriter writer) { IRunnableWithProgress runnable = new IRunnableWithProgress() { public void run(IProgressMonitor monitor) throws InvocationTargetException, InterruptedException { monitor.beginTask(MDEUIMessages.OpenLogDialog_message, IProgressMonitor.UNKNOWN); try { readLargeFile(writer); } catch (IOException e) { writer.println(MDEUIMessages.OpenLogDialog_cannotDisplay); } } }; ProgressMonitorDialog dialog = new ProgressMonitorDialog(getParentShell()); try { dialog.run(true, true, runnable); } catch (InvocationTargetException e) { } catch (InterruptedException e) { } } private void readFileWithMonitor(final PrintWriter writer) { IRunnableWithProgress runnable = new IRunnableWithProgress() { public void run(IProgressMonitor monitor) throws InvocationTargetException, InterruptedException { monitor.beginTask(MDEUIMessages.OpenLogDialog_message, IProgressMonitor.UNKNOWN); try { readFile(writer); } catch (IOException e) { writer.println(MDEUIMessages.OpenLogDialog_cannotDisplay); } } }; ProgressMonitorDialog dialog = new ProgressMonitorDialog(getParentShell()); try { dialog.run(true, true, runnable); } catch (InvocationTargetException e) { } catch (InterruptedException e) { } } //--------------- configuration handling -------------- /** * Stores the current state in the dialog settings. * * @since 2.0 */ private void storeSettings() { writeConfiguration(); } /** * Returns the dialog settings object used to share state between several * event detail dialogs. * * @return the dialog settings to be used */ private IDialogSettings getDialogSettings() { IDialogSettings settings = MDEPlugin.getDefault().getDialogSettings(); dialogSettings = settings.getSection(getClass().getName()); if (dialogSettings == null) dialogSettings = settings.addNewSection(getClass().getName()); return dialogSettings; } /** * Initializes itself from the dialog settings with the same state as at the * previous invocation. */ private void readConfiguration() { IDialogSettings s = getDialogSettings(); try { int x = s.getInt("x"); //$NON-NLS-1$ int y = s.getInt("y"); //$NON-NLS-1$ dialogLocation = new Point(x, y); x = s.getInt("width"); //$NON-NLS-1$ y = s.getInt("height"); //$NON-NLS-1$ dialogSize = new Point(x, y); } catch (NumberFormatException e) { dialogLocation = null; dialogSize = null; } } private void writeConfiguration() { IDialogSettings s = getDialogSettings(); Point location = getShell().getLocation(); s.put("x", location.x); //$NON-NLS-1$ s.put("y", location.y); //$NON-NLS-1$ Point size = getShell().getSize(); s.put("width", size.x); //$NON-NLS-1$ s.put("height", size.y); //$NON-NLS-1$ } }