All Downloads are FREE. Search and download functionalities are using the official Maven repository.

freemarker.template.Template Maven / Gradle / Ivy

There is a newer version: 0.4.3
Show newest version
/*
 * Copyright (c) 2003 The Visigoth Software Society. All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowledgement:
 *       "This product includes software developed by the
 *        Visigoth Software Society (http://www.visigoths.org/)."
 *    Alternately, this acknowledgement may appear in the software itself,
 *    if and wherever such third-party acknowledgements normally appear.
 *
 * 4. Neither the name "FreeMarker", "Visigoth", nor any of the names of the
 *    project contributors may be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact [email protected].
 *
 * 5. Products derived from this software may not be called "FreeMarker" or "Visigoth"
 *    nor may "FreeMarker" or "Visigoth" appear in their names
 *    without prior written permission of the Visigoth Software Society.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE VISIGOTH SOFTWARE SOCIETY OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Visigoth Software Society. For more
 * information on the Visigoth Software Society, please see
 * http://www.visigoths.org/
 */

package freemarker.template;

import java.io.*;
import java.util.*;
import javax.swing.tree.TreePath;
import freemarker.core.*;

import freemarker.debug.impl.DebuggerService;

/**
 * 

A core FreeMarker API that represents a compiled template. * Typically, you will use a {@link Configuration} object to instantiate a template. * *

      Configuration cfg = new Configuration();
      ...
      Template myTemplate = cfg.getTemplate("myTemplate.html");
   
* *

However, you can also construct a template directly by passing in to * the appropriate constructor a java.io.Reader instance that is set to * read the raw template text. The compiled template is * stored in an an efficient data structure for later use. * *

To render the template, i.e. to merge it with a data model, and * thus produce "cooked" output, call the process method. * *

Any error messages from exceptions thrown during compilation will be * included in the output stream and thrown back to the calling code. * To change this behavior, you can install custom exception handlers using * {@link Configurable#setTemplateExceptionHandler(TemplateExceptionHandler)} on * a Configuration object (for all templates belonging to a configuration) or on * a Template object (for a single template). * *

It's not legal to modify the values of FreeMarker settings: a) while the * template is executing; b) if the template object is already accessible from * multiple threads. * * @version $Id: Template.java,v 1.216.2.3 2006/03/10 17:49:02 revusky Exp $ */ public class Template extends Configurable { public static final String DEFAULT_NAMESPACE_PREFIX = "D"; public static final String NO_NS_PREFIX = "N"; private Map macros = new HashMap(); private List imports = new Vector(); private TemplateElement rootElement; private String encoding, defaultNS; private final String name; private final ArrayList lines = new ArrayList(); private Map prefixToNamespaceURILookup = new HashMap(); private Map namespaceURIToPrefixLookup = new HashMap(); /** * A prime constructor to which all other constructors should * delegate directly or indirectly. */ private Template(String name, Configuration cfg) { super(cfg != null ? cfg : Configuration.getDefaultConfiguration()); this.name = name; } /** * Constructs a template from a character stream. * * @param name the path of the template file relative to the directory what you use to store * the templates. See {@link #getName} for more details. * @param reader the character stream to read from. It will always be closed (Reader.close()). * @param cfg the Configuration object that this Template is associated with. * If this is null, the "default" {@link Configuration} object is used, * which is highly discouraged, because it can easily lead to * erroneous, unpredictable behaviour. * (See more {@link Configuration#getDefaultConfiguration() here...}) * @param encoding This is the encoding that we are supposed to be using. If this is * non-null (It's not actually necessary because we are using a Reader) then it is * checked against the encoding specified in the FTL header -- assuming that is specified, * and if they don't match a WrongEncodingException is thrown. */ public Template(String name, Reader reader, Configuration cfg, String encoding) throws IOException { this(name, cfg); this.encoding = encoding; if (!(reader instanceof BufferedReader)) { reader = new BufferedReader(reader, 0x1000); } LineTableBuilder ltb = new LineTableBuilder(reader); try { try { FMParser parser = new FMParser(this, ltb, getConfiguration().getStrictSyntaxMode(), getConfiguration().getWhitespaceStripping(), getConfiguration().getTagSyntax()); this.rootElement = parser.Root(); } catch (TokenMgrError exc) { throw new ParseException("Token manager error: " + exc, 0, 0); } } catch(ParseException e) { e.setTemplateName(name); throw e; } finally { ltb.close(); } DebuggerService.registerTemplate(this); namespaceURIToPrefixLookup = Collections.unmodifiableMap(namespaceURIToPrefixLookup); prefixToNamespaceURILookup = Collections.unmodifiableMap(prefixToNamespaceURILookup); } /** * This is equivalent to Template(name, reader, cfg, null) */ public Template(String name, Reader reader, Configuration cfg) throws IOException { this(name, reader, cfg, null); } /** * Constructs a template from a character stream. * * This is the same as the 3 parameter version when you pass null * as the cfg parameter. * * @deprecated This constructor uses the "default" {@link Configuration} * instance, which can easily lead to erroneous, unpredictable behaviour. * See more {@link Configuration#getDefaultConfiguration() here...}. */ public Template(String name, Reader reader) throws IOException { this(name, reader, null); } /** * This constructor is only used internally. */ Template(String name, TemplateElement root, Configuration config) { this(name, config); this.rootElement = root; DebuggerService.registerTemplate(this); } /** * Returns a trivial template, one that is just a single block of * plain text, no dynamic content. (Used by the cache module to create * unparsed templates.) * @param name the path of the template file relative to the directory what you use to store * the templates. See {@link #getName} for more details. * @param content the block of text that this template represents * @param config the configuration to which this template belongs */ static public Template getPlainTextTemplate(String name, String content, Configuration config) { Template template = new Template(name, config); TextBlock block = new TextBlock(content); template.rootElement = block; DebuggerService.registerTemplate(template); return template; } /** * Processes the template, using data from the map, and outputs * the resulting text to the supplied Writer The elements of the * map are converted to template models using the default object wrapper * returned by the {@link Configuration#getObjectWrapper() getObjectWrapper()} * method of the Configuration. * @param rootMap the root node of the data model. If null, an * empty data model is used. Can be any object that the effective object * wrapper can turn into a TemplateHashModel. Basically, simple and * beans wrapper can turn java.util.Map objects into hashes * and the Jython wrapper can turn both a PyDictionary as well as * any object that implements __getitem__ into a template hash. * Naturally, you can pass any object directly implementing * TemplateHashModel as well. * @param out a Writer to output the text to. * @throws TemplateException if an exception occurs during template processing * @throws IOException if an I/O exception occurs during writing to the writer. */ public void process(Object rootMap, Writer out) throws TemplateException, IOException { createProcessingEnvironment(rootMap, out, null).process(); } /** * Processes the template, using data from the root map object, and outputs * the resulting text to the supplied writer, using the supplied * object wrapper to convert map elements to template models. * @param rootMap the root node of the data model. If null, an * empty data model is used. Can be any object that the effective object * wrapper can turn into a TemplateHashModel Basically, simple and * beans wrapper can turn java.util.Map objects into hashes * and the Jython wrapper can turn both a PyDictionary as well as any * object that implements __getitem__ into a template hash. * Naturally, you can pass any object directly implementing * TemplateHashModel as well. * @param wrapper The object wrapper to use to wrap objects into * {@link TemplateModel} instances. If null, the default wrapper retrieved * by {@link Configurable#getObjectWrapper()} is used. * @param out the writer to output the text to. * @param rootNode The root node for recursive processing, this may be null. * * @throws TemplateException if an exception occurs during template processing * @throws IOException if an I/O exception occurs during writing to the writer. */ public void process(Object rootMap, Writer out, ObjectWrapper wrapper, TemplateNodeModel rootNode) throws TemplateException, IOException { Environment env = createProcessingEnvironment(rootMap, out, wrapper); if (rootNode != null) { env.setCurrentVisitorNode(rootNode); } env.process(); } /** * Processes the template, using data from the root map object, and outputs * the resulting text to the supplied writer, using the supplied * object wrapper to convert map elements to template models. * @param rootMap the root node of the data model. If null, an * empty data model is used. Can be any object that the effective object * wrapper can turn into a TemplateHashModel Basically, simple and * beans wrapper can turn java.util.Map objects into hashes * and the Jython wrapper can turn both a PyDictionary as well as any * object that implements __getitem__ into a template hash. * Naturally, you can pass any object directly implementing * TemplateHashModel as well. * @param wrapper The object wrapper to use to wrap objects into * {@link TemplateModel} instances. If null, the default wrapper retrieved * by {@link Configurable#getObjectWrapper()} is used. * @param out the writer to output the text to. * * @throws TemplateException if an exception occurs during template processing * @throws IOException if an I/O exception occurs during writing to the writer. */ public void process(Object rootMap, Writer out, ObjectWrapper wrapper) throws TemplateException, IOException { process(rootMap, out, wrapper, null); } /** * Creates a {@link freemarker.core.Environment Environment} object, * using this template, the data model provided as the root map object, and * the supplied object wrapper to convert map elements to template models. * You can then call Environment.process() on the returned environment * to set off the actual rendering. * Use this method if you want to do some special initialization on the environment * before template processing, or if you want to read the environment after template * processing. * *

Example: * *

This: *

    * Environment env = myTemplate.createProcessingEnvironment(root, out, null);
    * env.process();
    * 
* is equivalent with this: *
    * myTemplate.process(root, out);
    * 
* But with createProcessingEnvironment, you can manipulate the environment * before and after the processing: *
    * Environment env = myTemplate.createProcessingEnvironment(root, out);
    * env.include("include/common.ftl", null, true);  // before processing
    * env.process();
    * TemplateModel x = env.getVariable("x");  // after processing
    * 
* * @param rootMap the root node of the data model. If null, an * empty data model is used. Can be any object that the effective object * wrapper can turn into a TemplateHashModel Basically, simple and * beans wrapper can turn java.util.Map objects into hashes * and the Jython wrapper can turn both a PyDictionary as well as any * object that implements __getitem__ into a template hash. * Naturally, you can pass any object directly implementing * TemplateHashModel as well. * @param wrapper The object wrapper to use to wrap objects into * {@link TemplateModel} instances. If null, the default wrapper retrieved * by {@link Configurable#getObjectWrapper()} is used. * @param out the writer to output the text to. * @return the {@link freemarker.core.Environment Environment} object created for processing * @throws TemplateException if an exception occurs while setting up the Environment object. * @throws IOException if an exception occurs doing any auto-imports */ public Environment createProcessingEnvironment(Object rootMap, Writer out, ObjectWrapper wrapper) throws TemplateException, IOException { TemplateHashModel root = null; if(rootMap instanceof TemplateHashModel) { root = (TemplateHashModel)rootMap; } else { if(wrapper == null) { wrapper = getObjectWrapper(); } try { root = rootMap != null ? (TemplateHashModel)wrapper.wrap(rootMap) : new SimpleHash(wrapper); if(root == null) { throw new IllegalArgumentException(wrapper.getClass().getName() + " converted " + rootMap.getClass().getName() + " to null."); } } catch(ClassCastException e) { throw new IllegalArgumentException(wrapper.getClass().getName() + " could not convert " + rootMap.getClass().getName() + " to a TemplateHashModel."); } } return new Environment(this, root, out); } /** * Same as createProcessingEnvironment(rootMap, out, null). * @see #createProcessingEnvironment(Object rootMap, Writer out, ObjectWrapper wrapper) */ public Environment createProcessingEnvironment(Object rootMap, Writer out) throws TemplateException, IOException { return createProcessingEnvironment(rootMap, out, null); } /** * Returns a string representing the raw template * text in canonical form. */ public String toString() { StringWriter sw = new StringWriter(); try { dump(sw); } catch (IOException ioe) { throw new RuntimeException(ioe.getMessage()); } return sw.toString(); } /** * The path of the template file relative to the directory what you use to store the templates. * For example, if the real path of template is "/www/templates/community/forum.fm", * and you use ""/www/templates" as * {@link Configuration#setDirectoryForTemplateLoading "directoryForTemplateLoading"}, * then name should be "community/forum.fm". The name is used for example when you * use <include ...> and you give a path that is relative to the current * template, or in error messages when FreeMarker logs an error while it processes the template. */ public String getName() { return name; } /** * Returns the Configuration object associated with this template. */ public Configuration getConfiguration() { return (Configuration) getParent(); } /** * Sets the character encoding to use for * included files. Usually you don't set this value manually, * instead it is assigned to the template upon loading. */ public void setEncoding(String encoding) { this.encoding = encoding; } /** * Returns the character encoding used for reading included files. */ public String getEncoding() { return this.encoding; } /** * Dump the raw template in canonical form. */ public void dump(PrintStream ps) { ps.print(rootElement.getCanonicalForm()); } /** * Dump the raw template in canonical form. */ public void dump(Writer out) throws IOException { out.write(rootElement.getCanonicalForm()); } /** * Called by code internally to maintain * a table of macros */ public void addMacro(Macro macro) { macros.put(macro.getName(), macro); } /** * Called by code internally to maintain * a list of imports */ public void addImport(LibraryLoad ll) { imports.add(ll); } /** * Returns the template source at the location * specified by the coordinates given. * @param beginColumn the first column of the requested source, 1-based * @param beginLine the first line of the requested source, 1-based * @param endColumn the last column of the requested source, 1-based * @param endLine the last line of the requested source, 1-based * @see freemarker.core.TemplateObject#getSource() */ public String getSource(int beginColumn, int beginLine, int endColumn, int endLine) { // Our container is zero-based. --beginLine; --beginColumn; --endColumn; --endLine; StringBuffer buf = new StringBuffer(); for (int i = beginLine ; i<=endLine; i++) { if (i < lines.size()) { buf.append(lines.get(i)); } } int lastLineLength = lines.get(endLine).toString().length(); int trailingCharsToDelete = lastLineLength - endColumn -1; buf.delete(0, beginColumn); buf.delete(buf.length() - trailingCharsToDelete, buf.length()); return buf.toString(); } /** * This is a helper class that builds up the line table * info for us. */ private class LineTableBuilder extends FilterReader { StringBuffer lineBuf = new StringBuffer(); int lastChar; /** * @param r the character stream to wrap */ LineTableBuilder(Reader r) { super(r); } public int read() throws IOException { int c = in.read(); handleChar(c); return c; } public int read(char cbuf[], int off, int len) throws IOException { int numchars = in.read(cbuf, off, len); for (int i=off; i < off+numchars; i++) { char c = cbuf[i]; handleChar(c); } return numchars; } public void close() throws IOException { if (lineBuf.length() >0) { lines.add(lineBuf.toString()); lineBuf.setLength(0); } super.close(); } private void handleChar(int c) { if (c == '\n' || c == '\r') { if (lastChar == '\r' && c == '\n') { // CRLF under Windoze int lastIndex = lines.size() -1; String lastLine = (String) lines.get(lastIndex); lines.set(lastIndex, lastLine + '\n'); } else { lineBuf.append((char) c); lines.add(lineBuf.toString()); lineBuf.setLength(0); } } else if (c == '\t') { int numSpaces = 8 - (lineBuf.length() %8); for (int i=0; i




© 2015 - 2024 Weber Informatics LLC | Privacy Policy