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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License 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 freemarker.template.utility;

import java.io.IOException;
import java.io.Writer;
import java.util.Map;

import freemarker.core.Environment;
import freemarker.template.SimpleScalar;
import freemarker.template.TemplateModel;
import freemarker.template.TemplateModelException;
import freemarker.template.TemplateScalarModel;
import freemarker.template.TemplateTransformModel;

/**
 * A transform that captures the output of a block of FTL code and stores that in a variable.
 *
 * 

As this transform is initially present in the shared variable set, you can always * access it from the templates:

* *
 * <@capture_output var="captured">
 *   ...
 * </@capture_output>
 * 
* *

And later in the template you can use the captured output:

* * ${captured} * *

This transform requires one of three parameters: var, local, or global. * Each of them specifies the name of the variable that stores the captured output, but the first creates a * variable in a name-space (as <#assign>), the second creates a macro-local variable (as <#local>), * and the last creates a global variable (as <#global>). *

*

In the case of an assignment within a namespace, there is an optional parameter * namespace that indicates in which namespace to do the assignment. * if this is omitted, the current namespace is used, and this will be, by far, the most * common usage pattern.

* * @deprecated Use block-assignments instead, like <assign x>...</assign>. */ @Deprecated public class CaptureOutput implements TemplateTransformModel { @Override public Writer getWriter(final Writer out, final Map args) throws TemplateModelException { String errmsg = "Must specify the name of the variable in " + "which to capture the output with the 'var' or 'local' or 'global' parameter."; if (args == null) throw new TemplateModelException(errmsg); boolean local = false, global = false; final TemplateModel nsModel = (TemplateModel) args.get("namespace"); Object varNameModel = args.get("var"); if (varNameModel == null) { varNameModel = args.get("local"); if (varNameModel == null) { varNameModel = args.get("global"); global = true; } else { local = true; } if (varNameModel == null) { throw new TemplateModelException(errmsg); } } if (args.size() == 2) { if (nsModel == null) { throw new TemplateModelException("Second parameter can only be namespace"); } if (local) { throw new TemplateModelException("Cannot specify namespace for a local assignment"); } if (global) { throw new TemplateModelException("Cannot specify namespace for a global assignment"); } if (!(nsModel instanceof Environment.Namespace)) { throw new TemplateModelException("namespace parameter does not specify a namespace. It is a " + nsModel.getClass().getName()); } } else if (args.size() != 1) throw new TemplateModelException( "Bad parameters. Use only one of 'var' or 'local' or 'global' parameters."); if (!(varNameModel instanceof TemplateScalarModel)) { throw new TemplateModelException("'var' or 'local' or 'global' parameter doesn't evaluate to a string"); } final String varName = ((TemplateScalarModel) varNameModel).getAsString(); if (varName == null) { throw new TemplateModelException("'var' or 'local' or 'global' parameter evaluates to null string"); } final StringBuilder buf = new StringBuilder(); final Environment env = Environment.getCurrentEnvironment(); final boolean localVar = local; final boolean globalVar = global; return new Writer() { @Override public void write(char cbuf[], int off, int len) { buf.append(cbuf, off, len); } @Override public void flush() throws IOException { out.flush(); } @Override public void close() throws IOException { SimpleScalar result = new SimpleScalar(buf.toString()); try { if (localVar) { env.setLocalVariable(varName, result); } else if (globalVar) { env.setGlobalVariable(varName, result); } else { if (nsModel == null) { env.setVariable(varName, result); } else { ((Environment.Namespace) nsModel).put(varName, result); } } } catch (java.lang.IllegalStateException ise) { // if somebody uses 'local' outside a macro throw new IOException("Could not set variable " + varName + ": " + ise.getMessage()); } } }; } }




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