org.openapitools.codegen.templating.mustache.IndentedLambda Maven / Gradle / Ivy
/*
* Copyright 2018 OpenAPI-Generator Contributors (https://openapi-generator.tech)
* Copyright 2018 SmartBear Software
*
* 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
*
* https://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 org.openapitools.codegen.templating.mustache;
import com.samskivert.mustache.Mustache;
import com.samskivert.mustache.Template;
import org.apache.commons.lang3.StringUtils;
import java.io.IOException;
import java.io.Writer;
/**
* This naively prepends indention to all lines of a fragment.
*
* Generator authors may add helpers for explicitly adding prefixed spaces which fragments won't be aware of.
*
* Register:
*
* additionalProperties.put("indent4", new IndentedLambda(4));
* additionalProperties.put("indent8", new IndentedLambda(8));
*
*
* Use:
*
{@code
* {{#indent4}}{{>template}}{{/indent4}}
* {{#indent8}}{{>other_template}}{{/indent8}}
* }
*/
public class IndentedLambda implements Mustache.Lambda {
private final int prefixSpaceCount;
private final String prefix;
private final int spaceCode;
private final boolean indentFirstLine;
private final boolean skipEmptyLines;
/**
* Constructs a new instance of {@link IndentedLambda}, with an indent count of 4 spaces
*/
public IndentedLambda() {
this(4, " ", null, false, false);
}
/**
* Constructs a new instance of {@link IndentedLambda}, with customized indent count and intention character
*
* @param prefixSpaceCount The number of indented characters to apply as a prefix to a fragment.
* @param indentionCharacter String representation of the character used in the indent (e.g. " ", "\t", ".").
* @param indentFirstLine Whether to indent the first line or not. Usually this is handled by the template already.
*/
public IndentedLambda(int prefixSpaceCount, String indentionCharacter, boolean indentFirstLine, boolean skipEmptyLines) {
this(prefixSpaceCount, Character.codePointAt(indentionCharacter, 0), null, indentFirstLine, skipEmptyLines);
}
/**
* Constructs a new instance of {@link IndentedLambda}, with customized indent count and intention character
*
* @param prefixSpaceCount The number of indented characters to apply as a prefix to a fragment.
* @param indentionCharacter String representation of the character used in the indent (e.g. " ", "\t", ".").
* @param prefix An optional prefix to prepend before the line (useful for multi-line comments).
* @param indentFirstLine Whether to indent the first line or not. Usually this is handled by the template already.
*/
public IndentedLambda(int prefixSpaceCount, String indentionCharacter, String prefix, boolean indentFirstLine, boolean skipEmptyLines) {
this(prefixSpaceCount, Character.codePointAt(indentionCharacter, 0), prefix, indentFirstLine, skipEmptyLines);
}
/**
* Constructs a new instance of {@link IndentedLambda}
*
* @param prefixSpaceCount The number of indented characters to apply as a prefix to a fragment.
* @param indentionCodePoint Code point of the single character used for indentation.
* @param prefix An optional prefix to prepend before the line (useful for multi-line comments).
* @param indentFirstLine Whether to indent the first line or not. Usually this is handled by the template already.
*/
private IndentedLambda(int prefixSpaceCount, int indentionCodePoint, String prefix, boolean indentFirstLine, boolean skipEmptyLines) {
if (prefixSpaceCount <= 0) {
throw new IllegalArgumentException("prefixSpaceCount must be greater than 0");
}
if (!Character.isValidCodePoint(indentionCodePoint)) {
throw new IllegalArgumentException("indentionCodePoint is an invalid code point ");
}
this.prefixSpaceCount = prefixSpaceCount;
this.spaceCode = indentionCodePoint;
this.prefix = prefix;
this.indentFirstLine = indentFirstLine;
this.skipEmptyLines = skipEmptyLines;
}
@Override
public void execute(Template.Fragment fragment, Writer writer) throws IOException {
String text = fragment.execute();
if (text == null || text.length() == 0) {
return;
}
String prefixedIndention = StringUtils.repeat(new String(Character.toChars(spaceCode)), prefixSpaceCount);
StringBuilder sb = new StringBuilder();
// use \n instead of System.lineSeparator (e.g. \r\n in Windows) as templates use \n
String[] lines = text.split("\n", -1);
for (int i = 0; i < lines.length; i++) {
String line = lines[i];
// Mustache will apply correct indentation to the first line of a template (to match declaration location).
// So, we want to skip the first line.
if (this.indentFirstLine || i > 0) {
if (!this.skipEmptyLines || line.trim().length() > 0) {
sb.append(prefixedIndention);
}
if (prefix != null) sb.append(prefix);
}
sb.append(line);
// We've split on \n. We don't want to add an additional trailing line.
if (i < lines.length - 1) {
sb.append("\n");
}
}
writer.write(sb.toString());
}
}