From 759ac5f42c6aff901dbeede4fbf1a1d2e08cad0f Mon Sep 17 00:00:00 2001 From: Thomas Lenz Date: Wed, 4 Dec 2019 19:43:32 +0100 Subject: common EGIZ code-style refactoring --- .../gui/AbstractVelocityGuiFormBuilderImpl.java | 250 +++++++++++++++++++++ 1 file changed, 250 insertions(+) create mode 100644 eaaf_core/src/main/java/at/gv/egiz/eaaf/core/impl/gui/AbstractVelocityGuiFormBuilderImpl.java (limited to 'eaaf_core/src/main/java/at/gv/egiz/eaaf/core/impl/gui/AbstractVelocityGuiFormBuilderImpl.java') diff --git a/eaaf_core/src/main/java/at/gv/egiz/eaaf/core/impl/gui/AbstractVelocityGuiFormBuilderImpl.java b/eaaf_core/src/main/java/at/gv/egiz/eaaf/core/impl/gui/AbstractVelocityGuiFormBuilderImpl.java new file mode 100644 index 00000000..0ab5fa49 --- /dev/null +++ b/eaaf_core/src/main/java/at/gv/egiz/eaaf/core/impl/gui/AbstractVelocityGuiFormBuilderImpl.java @@ -0,0 +1,250 @@ +/* + * Copyright 2017 Graz University of Technology EAAF-Core Components has been developed in a + * cooperation between EGIZ, A-SIT Plus, A-SIT, and Graz University of Technology. + * + * Licensed under the EUPL, Version 1.2 or - as soon they will be approved by the European + * Commission - subsequent versions of the EUPL (the "Licence"); You may not use this work except in + * compliance with the Licence. You may obtain a copy of the Licence at: + * https://joinup.ec.europa.eu/news/understanding-eupl-v12 + * + * Unless required by applicable law or agreed to in writing, software distributed under the Licence + * is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express + * or implied. See the Licence for the specific language governing permissions and limitations under + * the Licence. + * + * This product combines work with different licenses. See the "NOTICE" text file for details on the + * various modules and licenses. The "NOTICE" text file is part of the distribution. Any derivative + * works that you distribute must include a readable copy of the "NOTICE" text file. +*/ + +package at.gv.egiz.eaaf.core.impl.gui; + +import java.io.BufferedReader; +import java.io.IOException; +import java.io.InputStream; +import java.io.InputStreamReader; +import java.io.StringWriter; +import java.util.Iterator; +import java.util.Map; +import java.util.Map.Entry; +import javax.servlet.http.HttpServletRequest; +import javax.servlet.http.HttpServletResponse; +import at.gv.egiz.eaaf.core.api.data.EAAFConstants; +import at.gv.egiz.eaaf.core.api.gui.IGuiBuilderConfiguration; +import at.gv.egiz.eaaf.core.api.gui.IVelocityGuiBuilderConfiguration; +import at.gv.egiz.eaaf.core.api.gui.IVelocityGuiFormBuilder; +import at.gv.egiz.eaaf.core.exceptions.GuiBuildException; +import at.gv.egiz.eaaf.core.impl.gui.velocity.VelocityProvider; +import org.apache.commons.lang3.StringUtils; +import org.apache.velocity.VelocityContext; +import org.apache.velocity.app.VelocityEngine; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +/** + * Abstract VeloCity based GUI builder implementation. + * + * @author tlenz + * + */ +public abstract class AbstractVelocityGuiFormBuilderImpl implements IVelocityGuiFormBuilder { + private static final Logger log = + LoggerFactory.getLogger(AbstractVelocityGuiFormBuilderImpl.class); + private static final String DEFAULT_CONTENT_TYPE = EAAFConstants.CONTENTTYPE_HTML_UTF8; + + private VelocityEngine engine; + + /** + * Velocity based GUI builder. + * + * @throws GuiBuildException In case of a error + */ + public AbstractVelocityGuiFormBuilderImpl() throws GuiBuildException { + try { + engine = VelocityProvider.getClassPathVelocityEngine(); + + } catch (final Exception e) { + log.error("Initialization of Velocity-Engine to render GUI components FAILED.", e); + throw new GuiBuildException( + "Initialization of Velocity-Engine to render GUI components FAILED.", e); + + } + + } + + @Override + public final void build(final HttpServletRequest httpReq, final HttpServletResponse httpResp, + final IGuiBuilderConfiguration config, final String loggerName) throws GuiBuildException { + if (config instanceof IVelocityGuiBuilderConfiguration) { + build(httpReq, httpResp, (IVelocityGuiBuilderConfiguration) config, loggerName); + } else { + throw new IllegalStateException(this.getClass().getName() + " needs a " + + IVelocityGuiBuilderConfiguration.class.getName()); + } + + + } + + @Override + public final void build(final HttpServletRequest httpReq, final HttpServletResponse httpResp, + final IGuiBuilderConfiguration config, final String contentType, final String loggerName) + throws GuiBuildException { + if (config instanceof IVelocityGuiBuilderConfiguration) { + build(httpReq, httpResp, (IVelocityGuiBuilderConfiguration) config, contentType, loggerName); + } else { + throw new IllegalStateException(this.getClass().getName() + " needs a " + + IVelocityGuiBuilderConfiguration.class.getName()); + } + + } + + @Override + public void build(final HttpServletRequest httpReq, final HttpServletResponse httpResp, + final IVelocityGuiBuilderConfiguration config, final String loggerName) + throws GuiBuildException { + build(httpReq, httpResp, config, getInternalContentType(config), loggerName); + + } + + @Override + public void build(final HttpServletRequest httpReq, final HttpServletResponse httpResp, + final IVelocityGuiBuilderConfiguration config, final String contentType, + final String loggerName) throws GuiBuildException { + + InputStream is = null; + try { + final String viewName = config.getViewName(); + is = getTemplateInputStream(config); + + // build Velocity Context from input paramters + final VelocityContext context = buildContextFromViewParams(config.getViewParameters()); + + // evaluate template + final StringWriter writer = new StringWriter(); + engine.evaluate(context, writer, loggerName, new BufferedReader(new InputStreamReader(is, "UTF-8"))); + + // write template to response + final byte[] content = writer.toString().getBytes("UTF-8"); + httpResp.setStatus(HttpServletResponse.SC_OK); + httpResp.setContentLength(content.length); + httpResp.setContentType(contentType); + httpResp.getOutputStream().write(content); + + if (log.isTraceEnabled()) { + log.trace("Write Content for viewName:" + viewName + ". Contentsize:" + + String.valueOf(content.length) + " BufferSize:" + httpResp.getBufferSize() + + " ContentType:" + contentType); + for (final String el : httpResp.getHeaderNames()) { + log.trace(" * Headername:" + el + " Value:" + httpResp.getHeader(el)); + } + + } + + } catch (final IOException e) { + log.error("GUI form-builder has an internal error.", e); + throw new GuiBuildException("GUI form-builder has an internal error.", e); + + } finally { + if (is != null) { + try { + is.close(); + + } catch (final IOException e) { + log.error("Can NOT close GUI-Template InputStream.", e); + + } + } + } + + } + + /** + * Generate a new {@link VelocityContext} and populate it with MOA-ID GUI parameters. + * + * @param config GUI builder config + * @return Context of Velocity engine + */ + @Override + public VelocityContext generateVelocityContextFromConfiguration( + final IVelocityGuiBuilderConfiguration config) { + return buildContextFromViewParams(config.getViewParameters()); + + } + + /** + * Load the template from different resources. + * + * @param config GUI builder config + * @return An {@link InputStream} but never null. The {@link InputStream} had to be closed be the + * invoking method + * @throws GuiBuildException In case of an error + */ + @Override + public InputStream getTemplateInputStream(final IVelocityGuiBuilderConfiguration config) + throws GuiBuildException { + InputStream is = config.getTemplate(config.getViewName()); + if (is == null) { + log.trace("Loading GUI template:" + config.getViewName() + " from default resources ... "); + is = getInternalTemplate(config); + + if (is == null) { + log.warn("No GUI with viewName:" + config.getViewName() + " FOUND."); + throw new GuiBuildException("No GUI with viewName:" + config.getViewName() + " FOUND."); + + } + } + return is; + + } + + /** + * Load an internal template from default resources. + * + * @param config GUI builder config + * @return Template that should be used + * @throws GuiBuildException in case of an error + */ + protected abstract InputStream getInternalTemplate(IVelocityGuiBuilderConfiguration config) + throws GuiBuildException; + + + protected String getInternalClasspathTemplateDir(final IVelocityGuiBuilderConfiguration config, + final String defaultClassPathDir) { + String dir = config.getClasspathTemplateDir(); + if (dir != null) { + if (!dir.endsWith("/")) { + dir += "/"; + } + + return dir; + + } else { + return defaultClassPathDir; + } + } + + private VelocityContext buildContextFromViewParams(final Map viewParams) { + final VelocityContext context = new VelocityContext(); + + if (viewParams != null) { + final Iterator> interator = viewParams.entrySet().iterator(); + while (interator.hasNext()) { + final Entry el = interator.next(); + context.put(el.getKey(), el.getValue()); + } + + } + + return context; + } + + private String getInternalContentType(final IGuiBuilderConfiguration config) { + if (StringUtils.isEmpty(config.getDefaultContentType())) { + return DEFAULT_CONTENT_TYPE; + } else { + return config.getDefaultContentType(); + } + + } + +} -- cgit v1.2.3