jena-arq/src/main/java/org/apache/jena/riot/out/NodeFormatterTTL_MultiLine.java

/**
 * 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 org.apache.jena.riot.out;

import static org.apache.jena.atlas.lib.Chars.CH_QUOTE1 ;
import static org.apache.jena.atlas.lib.Chars.CH_QUOTE2 ;

import org.apache.jena.atlas.io.AWriter ;
import org.apache.jena.atlas.io.IndentedWriter ;
import org.apache.jena.riot.out.quoted.QuotedStringOutput ;
import org.apache.jena.riot.out.quoted.QuotedStringOutputTTL_MultiLine ;
import org.apache.jena.riot.system.PrefixMap ;

/** 
 * Node formatter for pretty-printed Turtle.
 *  This {@link NodeFormatter} switches between " and ' quotes to avoid escapes.
 *  This code writes multiline literals with """ or '''. 
 */
public class NodeFormatterTTL_MultiLine extends NodeFormatterTTL {
    /// For '-quoted and "-quoted literals 
    private final QuotedStringOutput escapeProc2 = new QuotedStringOutputTTL_MultiLine(CH_QUOTE2) ;
    private final QuotedStringOutput escapeProc1 = new QuotedStringOutputTTL_MultiLine(CH_QUOTE1) ;

    private boolean writeAsMultiLine(AWriter w, String lex) {
        return ( lex.contains("\n") ) ;
    }

    public NodeFormatterTTL_MultiLine(String baseIRI, PrefixMap prefixMap) {
        super(baseIRI, prefixMap) ;
    }

    public NodeFormatterTTL_MultiLine(String baseIRI, PrefixMap prefixMap, NodeToLabel nodeToLabel) {
        super(baseIRI, prefixMap, nodeToLabel);
    }

    private Runnable noop = ()->{} ;

    @Override
    public void formatLitString(AWriter w, String lex)
    {
        if ( ! writeAsMultiLine(w, lex) ) {
            writeLexicalSingleLine(w, lex, noop);
            return ;
        }
        writeLexicalMultiLine(w, lex, noop) ; 
    }

    // To do ....
    @Override
    public void formatLitLang(AWriter w, String lex, String langTag) {
        if ( ! writeAsMultiLine(w, lex) ) {
            super.formatLitLang(w, lex, langTag);
            return ;
        }
        writeLexicalMultiLine(w, lex, ()->{ w.print('@') ; w.print(langTag) ; }) ;
    }

    @Override
    protected void writeLiteralLongForm(AWriter w, String lex, String datatypeURI)
    {
        if ( ! writeAsMultiLine(w, lex) ) {
            super.writeLiteralOneLine(w, lex, datatypeURI);
            return ;
        }
        writeLexicalMultiLine(w, lex, ()-> { w.print("^^") ; formatURI(w, datatypeURI) ; }) ;
    }

    private QuotedStringOutput chooseEscapeProcessor(String str) {
        QuotedStringOutput proc = escapeProc2 ;
        if ( str.indexOf(CH_QUOTE2) >= 0 && str.indexOf(CH_QUOTE1) < 0 )
            // Contains " but not ' so print using '-quotes.   
            proc = escapeProc1 ;
        return proc ;
    }

    /** Output a string and run the Runnable at the same indentation level */ 
    private void writeLexicalSingleLine(AWriter writer, String str, Runnable action) {
        QuotedStringOutput proc = chooseEscapeProcessor(str) ;
        proc.writeStr(writer, str); 
    }

    /** Output a string and run the Runnable at the same indentation level */ 
    private void writeLexicalMultiLine(AWriter writer, String str, Runnable action) {
        QuotedStringOutput escapeProc = chooseEscapeProcessor(str) ;
        int indent = -1 ; 
        IndentedWriter iw = null ;
        if ( writer instanceof IndentedWriter ) {
            iw = (IndentedWriter)writer ;
            iw.pad(); 
            indent = iw.getAbsoluteIndent() ;
            iw.setAbsoluteIndent(0);
        }
        escapeProc.writeStrMultiLine(writer, str) ;

        if ( action != null )
            action.run();
        if ( indent >= 0 )
            iw.setAbsoluteIndent(indent);
    }
}