/*
* Copyright (c) 2010, 2011, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package com.sun.tools.doclets.internal.toolkit;
import com.sun.tools.doclets.internal.toolkit.util.*;
/**
* A class to create content for javadoc output pages.
*
* @author Bhavesh Patel
*/
public abstract class Content {
/**
* Returns a string representation of the content.
*
* @return string representation of the content
*/
public String toString() {
StringBuilder contentBuilder = new StringBuilder();
write(contentBuilder);
return contentBuilder.toString();
}
/**
* Adds content to the existing content.
*
* @param content content that needs to be added
*/
public abstract void addContent(Content content);
/**
* Adds a string content to the existing content.
*
* @param stringContent the string content to be added
*/
public abstract void addContent(String stringContent);
/**
* Writes content to a StringBuilder.
*
*/
public abstract void write(StringBuilder contentBuilder);
/**
* Returns true if the content is empty.
*
* @return true if no content to be displayed else return false
*/
public abstract boolean isEmpty();
/**
* Returns true if the content is valid.
*
* @return true if the content is valid else return false
*/
public boolean isValid() {
return !isEmpty();
}
/**
* Checks for null values.
*
* @param t reference type to check for null values
* @return the reference type if not null or else throws a null pointer exception
*/
protected static <T> T nullCheck(T t) {
t.getClass();
return t;
}
/**
* Returns true if the content ends with a newline character. Empty content
* is considered as ending with new line.
*
* @param contentBuilder content to test for newline character at the end
* @return true if the content ends with newline.
*/
protected boolean endsWithNewLine(StringBuilder contentBuilder) {
int contentLength = contentBuilder.length();
if (contentLength == 0) {
return true;
}
int nlLength = DocletConstants.NL.length();
if (contentLength < nlLength) {
return false;
}
int contentIndex = contentLength - 1;
int nlIndex = nlLength - 1;
while (nlIndex >= 0) {
if (contentBuilder.charAt(contentIndex) != DocletConstants.NL.charAt(nlIndex)) {
return false;
}
contentIndex--;
nlIndex--;
}
return true;
}
}