Java tutorial
/* * Copyright 2012 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.explorer.cloudformation.wizard; import java.util.ArrayList; import java.util.Collection; import java.util.List; import java.util.Map; import java.util.regex.Matcher; import java.util.regex.Pattern; import org.eclipse.core.databinding.AggregateValidationStatus; import org.eclipse.core.databinding.DataBindingContext; import org.eclipse.core.databinding.observable.ChangeEvent; import org.eclipse.core.databinding.observable.IChangeListener; import org.eclipse.core.databinding.observable.Observables; import org.eclipse.core.databinding.validation.IValidator; import org.eclipse.core.databinding.validation.ValidationStatus; import org.eclipse.core.runtime.IStatus; import org.eclipse.core.runtime.Status; import org.eclipse.jface.databinding.swt.ISWTObservableValue; import org.eclipse.jface.databinding.swt.SWTObservables; import org.eclipse.jface.fieldassist.ControlDecoration; import org.eclipse.jface.fieldassist.FieldDecoration; import org.eclipse.jface.fieldassist.FieldDecorationRegistry; import org.eclipse.jface.layout.GridDataFactory; import org.eclipse.jface.layout.GridLayoutFactory; import org.eclipse.jface.wizard.WizardPage; import org.eclipse.swt.SWT; import org.eclipse.swt.custom.ScrolledComposite; import org.eclipse.swt.events.ControlAdapter; import org.eclipse.swt.events.ControlEvent; import org.eclipse.swt.graphics.Rectangle; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.widgets.Combo; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Label; import org.eclipse.swt.widgets.Text; import com.amazonaws.eclipse.core.AwsToolkitCore; import com.amazonaws.eclipse.databinding.ChainValidator; import com.amazonaws.eclipse.databinding.DecorationChangeListener; import com.amazonaws.eclipse.databinding.NotEmptyValidator; import com.amazonaws.services.cloudformation.model.TemplateParameter; /** * The second page in the create wizard second page */ public class CreateStackWizardSecondPage extends WizardPage { private static final String ALLOWED_VALUES = "AllowedValues"; private static final String MAX_LENGTH = "MaxLength"; private static final String MIN_LENGTH = "MinLength"; private static final String MAX_VALUE = "MaxValue"; private static final String MIN_VALUE = "MinValue"; private static final String CONSTRAINT_DESCRIPTION = "ConstraintDescription"; private static final String ALLOWED_PATTERN = "AllowedPattern"; CreateStackWizard wizard; private DataBindingContext bindingContext; private boolean complete = false; private static final String OK_MESSAGE = "Provide values for template parameters."; private Composite comp; private ScrolledComposite scrolledComp; protected CreateStackWizardSecondPage(CreateStackWizard wizard) { super("Fill in stack template parameters"); setMessage(OK_MESSAGE); this.wizard = wizard; } /* * (non-Javadoc) * * @see * org.eclipse.jface.dialogs.IDialogPage#createControl(org.eclipse.swt.widgets * .Composite) */ public void createControl(final Composite parent) { scrolledComp = new ScrolledComposite(parent, SWT.V_SCROLL); scrolledComp.setExpandHorizontal(true); scrolledComp.setExpandVertical(true); GridDataFactory.fillDefaults().grab(true, true).applyTo(scrolledComp); comp = new Composite(scrolledComp, SWT.None); GridDataFactory.fillDefaults().grab(true, true).applyTo(comp); GridLayoutFactory.fillDefaults().numColumns(2).applyTo(comp); scrolledComp.setContent(comp); scrolledComp.addControlListener(new ControlAdapter() { public void controlResized(ControlEvent e) { Rectangle r = scrolledComp.getClientArea(); scrolledComp.setMinSize(comp.computeSize(r.width, SWT.DEFAULT)); } }); setControl(scrolledComp); } private void createContents() { for (Control c : comp.getChildren()) { c.dispose(); } bindingContext = new DataBindingContext(); if (wizard.getDataModel().getTemplateParameters().isEmpty()) { setComplete(true); Label label = new Label(comp, SWT.NONE); label.setText("Selected template has no parameters"); label.setLayoutData(new GridData(SWT.LEFT, SWT.TOP, true, false, 2, 1)); } for (TemplateParameter param : wizard.getDataModel().getTemplateParameters()) { createParameterSection(comp, param); } // Finally provide aggregate status reporting for the entire wizard page final AggregateValidationStatus aggregateValidationStatus = new AggregateValidationStatus(bindingContext, AggregateValidationStatus.MAX_SEVERITY); aggregateValidationStatus.addChangeListener(new IChangeListener() { public void handleChange(ChangeEvent event) { Object value = aggregateValidationStatus.getValue(); if (value instanceof IStatus == false) return; IStatus status = (IStatus) value; if (status.isOK()) { setErrorMessage(null); setMessage(OK_MESSAGE, Status.OK); } else if (status.getSeverity() == Status.WARNING) { setErrorMessage(null); setMessage(status.getMessage(), Status.WARNING); } else if (status.getSeverity() == Status.ERROR) { setErrorMessage(status.getMessage()); } setComplete(status.isOK()); } }); comp.layout(); Rectangle r = scrolledComp.getClientArea(); scrolledComp.setMinSize(comp.computeSize(r.width, SWT.DEFAULT)); } @Override public void setVisible(boolean visible) { if (visible) { createContents(); } super.setVisible(true); } @Override public boolean isPageComplete() { return complete; } private void setComplete(boolean complete) { this.complete = complete; if (getWizard().getContainer() != null) getWizard().getContainer().updateButtons(); } @SuppressWarnings({ "rawtypes", "unchecked" }) private void createParameterSection(Composite comp, TemplateParameter param) { Map parameterMap = (Map) wizard.getDataModel().getTemplate().get("Parameters"); // Unfortunately, we have to manually adjust for field decorations FieldDecoration fieldDecoration = FieldDecorationRegistry.getDefault() .getFieldDecoration(FieldDecorationRegistry.DEC_ERROR); int fieldDecorationWidth = fieldDecoration.getImage().getBounds().width; Control paramControl = null; ISWTObservableValue observeParameter = null; ChainValidator<String> validationStatusProvider = null; if (parameterMap.containsKey(param.getParameterKey())) { Label label = new Label(comp, SWT.None); label.setText(param.getParameterKey()); Map paramMap = (Map) parameterMap.get(param.getParameterKey()); // Update the default value in the model. if (wizard.getDataModel().getParameterValues().get(param.getParameterKey()) == null) { wizard.getDataModel().getParameterValues().put(param.getParameterKey(), param.getDefaultValue()); } // If the template enumerates allowed values, present them as a // combo drop down if (paramMap.containsKey(ALLOWED_VALUES)) { Combo combo = new Combo(comp, SWT.DROP_DOWN | SWT.READ_ONLY); Collection<String> allowedValues = (Collection<String>) paramMap.get(ALLOWED_VALUES); GridDataFactory.fillDefaults().grab(true, false).indent(fieldDecorationWidth, 0).applyTo(combo); combo.setItems(allowedValues.toArray(new String[allowedValues.size()])); observeParameter = SWTObservables.observeSelection(combo); paramControl = combo; } else { // Otherwise, just use a text field with validation constraints Text text = new Text(comp, SWT.BORDER); GridDataFactory.fillDefaults().grab(true, false).indent(fieldDecorationWidth, 0).applyTo(text); observeParameter = SWTObservables.observeText(text, SWT.Modify); paramControl = text; // Add validators for the constraints listed in the template List<IValidator> validators = new ArrayList<IValidator>(); validators.add(new NotEmptyValidator("Please enter a value for " + param.getParameterKey())); if (paramMap.containsKey(ALLOWED_PATTERN)) { String pattern = (String) paramMap.get(ALLOWED_PATTERN); Pattern p = Pattern.compile(pattern); validators.add(new PatternValidator(p, param.getParameterKey() + ": " + (String) paramMap.get(CONSTRAINT_DESCRIPTION))); } if (paramMap.containsKey(MIN_LENGTH)) { validators.add(new MinLengthValidator(Integer.parseInt((String) paramMap.get(MIN_LENGTH)), param.getParameterKey())); } if (paramMap.containsKey(MAX_LENGTH)) { validators.add(new MaxLengthValidator(Integer.parseInt((String) paramMap.get(MAX_LENGTH)), param.getParameterKey())); } if (paramMap.containsKey(MIN_VALUE)) { validators.add(new MinValueValidator(Integer.parseInt((String) paramMap.get(MIN_VALUE)), param.getParameterKey())); } if (paramMap.containsKey(MAX_VALUE)) { validators.add(new MaxValueValidator(Integer.parseInt((String) paramMap.get(MAX_VALUE)), param.getParameterKey())); } if (!validators.isEmpty()) { validationStatusProvider = new ChainValidator<String>(observeParameter, validators.toArray(new IValidator[validators.size()])); } } } else { AwsToolkitCore.getDefault().logException("No parameter map object found for " + param.getParameterKey(), null); return; } if (param.getDescription() != null) { Label description = new Label(comp, SWT.WRAP); GridDataFactory.fillDefaults().grab(true, false).span(2, 1).indent(0, -8).applyTo(description); description.setText(param.getDescription()); description.setForeground(Display.getDefault().getSystemColor(SWT.COLOR_DARK_GRAY)); } bindingContext.bindValue(observeParameter, Observables.observeMapEntry( wizard.getDataModel().getParameterValues(), param.getParameterKey(), String.class)); if (validationStatusProvider != null) { bindingContext.addValidationStatusProvider(validationStatusProvider); ControlDecoration decoration = new ControlDecoration(paramControl, SWT.TOP | SWT.LEFT); decoration.setDescriptionText("Invalid value"); decoration.setImage(fieldDecoration.getImage()); new DecorationChangeListener(decoration, validationStatusProvider.getValidationStatus()); } } private final class PatternValidator implements IValidator { private Pattern pattern; private String errorMessage; private PatternValidator(Pattern pattern, String errorMessage) { this.pattern = pattern; this.errorMessage = errorMessage; } public IStatus validate(Object value) { Matcher matcher = pattern.matcher((CharSequence) value); if (matcher.matches()) { return ValidationStatus.ok(); } else { return ValidationStatus.error(errorMessage); } } } private final class MaxLengthValidator implements IValidator { private int maxLength; private String fieldName; private MaxLengthValidator(int maxLength, String fieldName) { super(); this.maxLength = maxLength; this.fieldName = fieldName; } public IStatus validate(Object value) { if (((String) value).length() > maxLength) { return ValidationStatus.error(fieldName + " must be at most " + maxLength + " characters long"); } else { return ValidationStatus.ok(); } } } private final class MinLengthValidator implements IValidator { private int minLength; private String fieldName; private MinLengthValidator(int minLength, String fieldName) { super(); this.minLength = minLength; this.fieldName = fieldName; } public IStatus validate(Object value) { if (((String) value).length() < minLength) { return ValidationStatus.error(fieldName + " must be at least " + minLength + " characters long"); } else { return ValidationStatus.ok(); } } } private final class MinValueValidator implements IValidator { private int minValue; private String fieldName; private MinValueValidator(int minValue, String fieldName) { super(); this.minValue = minValue; this.fieldName = fieldName; } public IStatus validate(Object value) { String string = (String) value; try { if (Integer.parseInt(string) < minValue) { return ValidationStatus.error(fieldName + " must be at least " + minValue); } else { return ValidationStatus.ok(); } } catch (Exception e) { return ValidationStatus.error(fieldName + " must be at least " + minValue); } } } private final class MaxValueValidator implements IValidator { private int maxValue; private String fieldName; private MaxValueValidator(int maxValue, String fieldName) { super(); this.maxValue = maxValue; this.fieldName = fieldName; } public IStatus validate(Object value) { String string = (String) value; try { if (Integer.parseInt(string) > maxValue) { return ValidationStatus.error(fieldName + " must be at most " + maxValue); } else { return ValidationStatus.ok(); } } catch (Exception e) { return ValidationStatus.error(fieldName + " must be at most " + maxValue); } } } }