Java tutorial
/* * Copyright 2008-2011 Amazon Technologies, Inc. * * 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://aws.amazon.com/apache2.0 * * This file 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.amazonaws.eclipse.ec2.ui.ebs; import org.eclipse.core.runtime.Status; import org.eclipse.jface.dialogs.Dialog; import org.eclipse.jface.dialogs.IDialogConstants; import org.eclipse.swt.SWT; import org.eclipse.swt.events.SelectionEvent; import org.eclipse.swt.events.SelectionListener; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Button; import org.eclipse.swt.widgets.Combo; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import org.eclipse.swt.widgets.Label; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Spinner; import org.eclipse.ui.statushandlers.StatusManager; import com.amazonaws.eclipse.core.AWSClientFactory; import com.amazonaws.eclipse.core.AwsToolkitCore; import com.amazonaws.eclipse.ec2.Ec2Plugin; import com.amazonaws.services.ec2.AmazonEC2; import com.amazonaws.services.ec2.model.AvailabilityZone; import com.amazonaws.services.ec2.model.Instance; import com.amazonaws.services.ec2.model.Snapshot; /** * A dialog that allows a user to enter information for creating a new EBS * volume. */ public class CreateNewVolumeDialog extends Dialog { /** Shared client factory */ private AWSClientFactory clientFactory = AwsToolkitCore.getClientFactory(); /** Spinner control for specifying how large of a volume to create */ private Spinner sizeSpinner; /** Combo box to select what availability zone to create a volume in */ private Combo availabilityZoneCombo; /** The volume size */ private int size; /** The availability zone to create a volume in */ private String availabilityZone; /** The radio button for creating a volume by size */ private Button emptyVolumeRadioButton; /** The radio button for creating a volume from a snapshot */ private Button useSnapshotRadioButton; /** The snapshot selection table */ private SnapshotSelectionTable snapshotSelectionComposite; /** The id of the selected snapshot */ private String snapshotId; /** * The device the new volume should be attached to. This is only * set if the the new volume being created is explicitly being created * to be attached to a specific instance. */ private String device; /** * The instance to which this new volume is being attached. This is only * present if the new volume being created is explicitly being created to be * attached to an instance, and isn't set during the normal * "Create New Volume" workflow. */ private Instance instance = null; private Combo deviceCombo; /** * Creates a new dialog ready to be opened to collect information from the * user on how to create a new EBS volume. * * @param parentShell * The parent shell for this new dialog window. */ public CreateNewVolumeDialog(Shell parentShell) { super(parentShell); } /** * Creates a new dialog ready to be opened to collect information from the * user on how to create a new EBS volume which will be attached to the * specified instance. When creating a new volume explicitly for attaching * it to a specific instance, certain parts of the dialog are different, * such as the availability zone being locked down to the zone the specified * instance is in, and a new Combo box is present that allows the user to * select what device the new EBS volume should be attached as. * * @param parentShell * The parent shell for this new dialog window. * @param instance * The instance that the new EBS volume will be attached to. */ public CreateNewVolumeDialog(Shell parentShell, Instance instance) { this(parentShell); this.instance = instance; } /** * Returns the selected volume size. This method can only be called after * the dialog's Ok button has been pressed. * * @return The selected volume size. */ public int getSize() { return size; } /** * Returns the selected availability zone. This method can only be called * after the dialog's Ok button has been pressed. * * @return The selected availability zone. */ public String getAvailabilityZone() { return availabilityZone; } /** * Returns the selected device that this new volume should be attached to. * * @return The selected device that this new volume should be attached to. */ public String getDevice() { return device; } /** * Returns the selected snapshot id. This method can only be called after * the dialog's Ok button has been pressed. * * @return The selected snapshot id. */ public String getSnapshotId() { return snapshotId; } /* * Dialog Interface */ /* (non-Javadoc) * @see org.eclipse.jface.dialogs.Dialog#createDialogArea(org.eclipse.swt.widgets.Composite) */ @Override protected Control createDialogArea(Composite parent) { Composite composite = new Composite(parent, SWT.NONE); composite.setLayout(new GridLayout(2, false)); GridData gridData; SelectionListener selectionListener = new SelectionListener() { public void widgetDefaultSelected(SelectionEvent e) { } public void widgetSelected(SelectionEvent e) { updateControls(); } }; /* * If we aren't creating this new volume explicitly to attach it to * a specific instance, then we can let the user select an availability * zone, otherwise we need to lock it down to the availability zone of the * instance that will be attaching this new volume. */ newLabel("Availability Zone:", composite); if (instance == null) { availabilityZoneCombo = new Combo(composite, SWT.READ_ONLY); availabilityZoneCombo.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); populateAvailabilityZoneCombo(); } else { newLabel(instance.getPlacement().getAvailabilityZone(), composite); } /* * If we are creating this new volume explicitly for attaching it to a * specified instance, then we also need to let the user select the * device they want the volume attached as. */ if (instance != null) { newLabel("Device:", composite); deviceCombo = new Combo(composite, SWT.READ_ONLY); deviceCombo.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); String devicePrefix = "/dev/sd"; for (char c = 'b'; c <= 'z'; c++) { deviceCombo.add(devicePrefix + c); } deviceCombo.setText("/dev/sdh"); } emptyVolumeRadioButton = new Button(composite, SWT.RADIO); emptyVolumeRadioButton.setText("Create empty volume by size (GB):"); gridData = new GridData(GridData.FILL_HORIZONTAL); gridData.horizontalSpan = 1; emptyVolumeRadioButton.setLayoutData(gridData); emptyVolumeRadioButton.addSelectionListener(selectionListener); sizeSpinner = new Spinner(composite, SWT.NONE); sizeSpinner.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); sizeSpinner.setMinimum(1); sizeSpinner.setMaximum(1024); sizeSpinner.setEnabled(false); useSnapshotRadioButton = new Button(composite, SWT.RADIO); useSnapshotRadioButton.setText("Or create volume from existing snapshot:"); gridData = new GridData(GridData.FILL_HORIZONTAL); gridData.horizontalSpan = 2; useSnapshotRadioButton.setLayoutData(gridData); useSnapshotRadioButton.addSelectionListener(selectionListener); snapshotSelectionComposite = new SnapshotSelectionTable(composite); gridData = new GridData(GridData.FILL_HORIZONTAL); gridData.horizontalSpan = 2; gridData.horizontalIndent = 15; gridData.heightHint = 150; snapshotSelectionComposite.setLayoutData(gridData); snapshotSelectionComposite.addSelectionListener(new SelectionListener() { public void widgetDefaultSelected(SelectionEvent e) { } public void widgetSelected(SelectionEvent e) { updateControls(); } }); return composite; } /** * Populates the availability zone combo box with the available zones. */ private void populateAvailabilityZoneCombo() { if (availabilityZoneCombo == null) return; try { AmazonEC2 ec2 = Ec2Plugin.getDefault().getDefaultEC2Client(); for (AvailabilityZone zone : ec2.describeAvailabilityZones().getAvailabilityZones()) { availabilityZoneCombo.add(zone.getZoneName()); } availabilityZoneCombo.select(0); } catch (Exception e) { Status status = new Status(Status.ERROR, Ec2Plugin.PLUGIN_ID, "Unable to list availability zones"); StatusManager.getManager().handle(status, StatusManager.LOG); } } /* (non-Javadoc) * @see org.eclipse.jface.dialogs.Dialog#create() */ @Override public void create() { super.create(); String title = null; if (instance == null) { title = "Create New EBS Volume"; } else { title = "Attach New EBS Volume"; } getShell().setText(title); emptyVolumeRadioButton.setSelection(true); updateControls(); } /* (non-Javadoc) * @see org.eclipse.jface.dialogs.Dialog#okPressed() */ @Override protected void okPressed() { size = sizeSpinner.getSelection(); if (availabilityZoneCombo != null) { availabilityZone = availabilityZoneCombo.getText(); } if (deviceCombo != null) { device = deviceCombo.getText(); } Snapshot selectedSnapshot = snapshotSelectionComposite.getSelectedSnapshot(); if (selectedSnapshot != null) { snapshotId = selectedSnapshot.getSnapshotId(); } super.okPressed(); } /* * Private Interface */ private void updateControls() { boolean creatingFromSnapshot = useSnapshotRadioButton.getSelection(); Button okButton = getButton(IDialogConstants.OK_ID); snapshotSelectionComposite.setEnabled(creatingFromSnapshot); sizeSpinner.setEnabled(!creatingFromSnapshot); if (creatingFromSnapshot) { if (okButton != null) { Snapshot snapshot = snapshotSelectionComposite.getSelectedSnapshot(); okButton.setEnabled(snapshot != null); } } else { snapshotSelectionComposite.clearSelection(); if (okButton != null) okButton.setEnabled(true); } } private Label newLabel(String text, Composite parent) { Label l = new Label(parent, SWT.NONE); l.setText(text); GridData gridData = new GridData(GridData.FILL_HORIZONTAL); gridData.verticalAlignment = GridData.VERTICAL_ALIGN_BEGINNING; l.setLayoutData(gridData); return l; } }