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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 ad
* ditional 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.writer ;
import static org.apache.jena.riot.writer.WriterConst.GAP_P_O ;
import static org.apache.jena.riot.writer.WriterConst.GAP_S_P ;
import static org.apache.jena.riot.writer.WriterConst.INDENT_OBJECT ;
import static org.apache.jena.riot.writer.WriterConst.INDENT_PREDICATE ;
import static org.apache.jena.riot.writer.WriterConst.LONG_PREDICATE ;
import static org.apache.jena.riot.writer.WriterConst.LONG_SUBJECT ;
import static org.apache.jena.riot.writer.WriterConst.MIN_PREDICATE ;
import static org.apache.jena.riot.writer.WriterConst.OBJECT_LISTS ;
import static org.apache.jena.riot.writer.WriterConst.RDF_First ;
import static org.apache.jena.riot.writer.WriterConst.RDF_Nil ;
import static org.apache.jena.riot.writer.WriterConst.RDF_Rest ;
import static org.apache.jena.riot.writer.WriterConst.RDF_type ;
import static org.apache.jena.riot.writer.WriterConst.rdfNS ;
import java.util.* ;
import org.apache.jena.atlas.io.IndentedWriter ;
import org.apache.jena.atlas.iterator.Iter ;
import org.apache.jena.atlas.lib.InternalErrorException ;
import org.apache.jena.atlas.lib.Pair ;
import org.apache.jena.atlas.lib.SetUtils ;
import org.apache.jena.graph.Graph ;
import org.apache.jena.graph.Node ;
import org.apache.jena.graph.Triple ;
import org.apache.jena.riot.RIOT ;
import org.apache.jena.riot.other.GLib ;
import org.apache.jena.riot.out.NodeFormatter ;
import org.apache.jena.riot.out.NodeFormatterTTL ;
import org.apache.jena.riot.out.NodeFormatterTTL_MultiLine ;
import org.apache.jena.riot.out.NodeToLabel ;
import org.apache.jena.riot.system.PrefixMap ;
import org.apache.jena.riot.system.PrefixMapFactory ;
import org.apache.jena.riot.system.RiotLib ;
import org.apache.jena.sparql.core.DatasetGraph ;
import org.apache.jena.sparql.core.Quad ;
import org.apache.jena.sparql.util.Context ;
import org.apache.jena.util.iterator.ExtendedIterator ;
import org.apache.jena.vocabulary.RDF ;
import org.apache.jena.vocabulary.RDFS ;
/**
* Base class to support the pretty forms of Turtle-related languages (Turtle, TriG)
*/
public abstract class TurtleShell {
protected final IndentedWriter out ;
protected final NodeFormatter nodeFmt ;
protected final PrefixMap prefixMap ;
protected final String baseURI ;
protected final Context context ;
protected final PrefixStyle prefixStyle;
static PrefixStyle dftPrefixStyle = PrefixStyle.AT;
enum PrefixStyle {
AT, SPARQL ;
public static PrefixStyle create(String label) {
String s = label.toLowerCase() ;
switch(s) {
case "rdf_10": case "rdf10": case "n3": case "at":
return PrefixStyle.AT ;
case "rdf_11": case "rdf11": case "sparql":
return PrefixStyle.SPARQL ;
}
return null;
}
};
protected TurtleShell(IndentedWriter out, PrefixMap pmap, String baseURI, NodeFormatter nodeFmt, Context context) {
this.out = out ;
if ( pmap == null )
pmap = PrefixMapFactory.emptyPrefixMap() ;
this.prefixMap = pmap ;
this.baseURI = baseURI ;
this.nodeFmt = nodeFmt ;
this.context = context;
this.prefixStyle = prefixStyle(context) ;
}
// Determine the prefix style (applies to BASE as well).
private static PrefixStyle prefixStyle(Context context) {
Object x = context.get(RIOT.symTurtlePrefixStyle) ;
if ( x instanceof String ) {
String s = (String)x ;
PrefixStyle style = PrefixStyle.create(s);
return style == null ? dftPrefixStyle : style;
}
if ( x instanceof PrefixStyle )
return (PrefixStyle)x ;
// Default choice; includes null in context.
return dftPrefixStyle;
}
protected TurtleShell(IndentedWriter out, PrefixMap pmap, String baseURI, Context context) {
this(out, pmap, baseURI, createNodeFormatter(pmap,baseURI,context), context) ;
}
static public NodeFormatter createNodeFormatter(PrefixMap pmap, String baseURI, Context context) {
if ( context != null && context.isTrue(RIOT.multilineLiterals) )
return new NodeFormatterTTL_MultiLine(baseURI, pmap, NodeToLabel.createScopeByDocument()) ;
else
return new NodeFormatterTTL(baseURI, pmap, NodeToLabel.createScopeByDocument()) ;
}
protected void writeBase(String base) {
RiotLib.writeBase(out, base, prefixStyle==PrefixStyle.SPARQL) ;
}
protected void writePrefixes(PrefixMap prefixMap) {
RiotLib.writePrefixes(out, prefixMap, prefixStyle==PrefixStyle.SPARQL) ;
}
/** Write graph in Turtle syntax (or part of TriG) */
protected void writeGraphTTL(Graph graph) {
ShellGraph x = new ShellGraph(graph, null, null) ;
x.writeGraph() ;
}
/** Write graph in Turtle syntax (or part of TriG). graphName is null for default graph. */
protected void writeGraphTTL(DatasetGraph dsg, Node graphName) {
Graph g = (graphName == null || Quad.isDefaultGraph(graphName))
? dsg.getDefaultGraph()
: dsg.getGraph(graphName) ;
ShellGraph x = new ShellGraph(g, graphName, dsg) ;
x.writeGraph() ;
}
// Write one graph - using an inner object class to isolate
// the state variables for writing a single graph.
private final class ShellGraph {
// Dataset (for writing graphs indatasets) -- may be null
private final DatasetGraph dsg ;
private final Collection graphNames ;
private final Node graphName ;
private final Graph graph ;
// Blank nodes that have one incoming triple
private /*final*/ Set nestedObjects ;
private final Set nestedObjectsWritten ;
// Blank node subjects that are not referenced as objects or graph names
// excluding unlnked lists.
private final Set freeBnodes ;
// The head node in each well-formed list -> list elements
private final Map> lists ;
// List that do not have any incoming triples
private final Map> freeLists ;
// Lists that have more than one incoming triple
private final Map> nLinkedLists ;
// All nodes that are part of list structures.
private final Collection listElts ;
// Allow lists and nest bnode objects.
// This is true for the main pretty printing then
// false when we are clearing up unwritten triples.
private boolean allowDeepPretty = true ;
private ShellGraph(Graph graph, Node graphName, DatasetGraph dsg) {
this.dsg = dsg ;
this.graphName = graphName ;
this.graphNames = (dsg != null) ? Iter.toSet(dsg.listGraphNodes()) : null ;
this.graph = graph ;
this.nestedObjects = new HashSet<>() ;
this.nestedObjectsWritten = new HashSet<>() ;
this.freeBnodes = new HashSet<>() ;
this.lists = new HashMap<>() ;
this.freeLists = new HashMap<>() ;
this.nLinkedLists = new HashMap<>() ;
this.listElts = new HashSet<>() ;
this.allowDeepPretty = true ;
// Must be in this order.
findLists() ;
findBNodesSyntax1() ;
// Stop head of lists printed as triples going all the way to the
// good part.
nestedObjects.removeAll(listElts) ;
//printDetails() ;
}
// Debug
private void printDetails() {
printDetails("nestedObjects", nestedObjects) ;
//printDetails("nestedObjectsWritten", nestedObjectsWritten) ;
printDetails("freeBnodes", freeBnodes) ;
printDetails("lists", lists) ;
printDetails("freeLists", freeLists) ;
printDetails("nLinkedLists", nLinkedLists) ;
printDetails("listElts", listElts) ;
}
private void printDetails(String label, Map> map) {
System.err.print("## ") ;
System.err.print(label) ;
System.err.print(" = ") ;
System.err.println(map) ;
}
private void printDetails(String label, Collection nodes) {
System.err.print("## ") ;
System.err.print(label) ;
System.err.print(" = ") ;
System.err.println(nodes) ;
}
// Debug
private ShellGraph(Graph graph) {
this(graph, null, null) ;
}
// ---- Data access
/** Get all the triples for the graph.find */
private List triples(Node s, Node p, Node o) {
List acc = new ArrayList<>() ;
RiotLib.accTriples(acc, graph, s, p, o) ;
return acc ;
}
/** Get exactly one triple or null for none or more than one. */
private Triple triple1(Node s, Node p, Node o) {
if ( dsg != null )
return RiotLib.triple1(dsg, s, p, o) ;
else
return RiotLib.triple1(graph, s, p, o) ;
}
/** Get exactly one triple, or null for none or more than one. */
private Triple triple1(DatasetGraph dsg, Node s, Node p, Node o) {
Iterator iter = dsg.find(Node.ANY, s, p, o) ;
if ( !iter.hasNext() )
return null ;
Quad q = iter.next() ;
if ( iter.hasNext() )
return null ;
return q.asTriple() ;
}
private long countTriples(Node s, Node p, Node o) {
if ( dsg != null )
return RiotLib.countTriples(dsg, s, p, o) ;
else
return RiotLib.countTriples(graph, s, p, o) ;
}
private ExtendedIterator find(Node s, Node p, Node o) {
return graph.find(s, p, o) ;
}
/** returns 0,1,2 (where 2 really means "more than 1") */
private int inLinks(Node obj) {
if ( dsg != null ) {
Iterator iter = dsg.find(Node.ANY, Node.ANY, Node.ANY, obj) ;
return count012(iter) ;
} else {
ExtendedIterator iter = graph.find(Node.ANY, Node.ANY, obj) ;
try { return count012(iter) ; }
finally { iter.close() ; }
}
}
/** returns 0,1,2 (where 2 really means "more than 1") */
private int occursAsSubject(Node subj) {
if ( dsg != null ) {
Iterator iter = dsg.find(Node.ANY, subj, Node.ANY, Node.ANY) ;
return count012(iter) ;
} else {
ExtendedIterator iter = graph.find(subj, Node.ANY, Node.ANY) ;
try { return count012(iter) ; }
finally { iter.close() ; }
}
}
private int count012(Iterator iter) {
if ( !iter.hasNext() )
return 0 ;
iter.next() ;
if ( !iter.hasNext() )
return 1 ;
return 2 ;
}
/** Check whether a node is used only in the graph we're working on */
private boolean containedInOneGraph(Node node) {
if ( dsg == null )
// Single graph
return true ;
if ( graphNames.contains(node) )
// Used as a graph name.
return false ;
Iterator iter = dsg.find(Node.ANY, node, Node.ANY, Node.ANY) ;
if ( ! quadsThisGraph(iter) )
return false ;
iter = dsg.find(Node.ANY, Node.ANY, node, Node.ANY) ;
if ( ! quadsThisGraph(iter) )
return false ;
iter = dsg.find(Node.ANY, Node.ANY, Node.ANY, node) ;
if ( ! quadsThisGraph(iter) )
return false ;
return true ;
}
/** Check whether an iterator of quads is all in the same graph (dataset assumed) */
private boolean quadsThisGraph(Iterator iter) {
if ( ! iter.hasNext() )
// Empty iterator
return true ;
Quad q = iter.next() ;
Node gn = q.getGraph() ;
// Test first quad - both default graph (various forms) or same named graph
if ( isDefaultGraph(gn) ) {
if ( ! isDefaultGraph(graphName) )
return false ;
} else {
if ( ! Objects.equals(gn, graphName) )
// Not both same named graph
return false ;
}
// Check rest of iterator.
for ( ; iter.hasNext() ; ) {
Quad q2 = iter.next() ;
if ( ! Objects.equals(gn, q2.getGraph()) )
return false ;
}
return true ;
}
private boolean isDefaultGraph(Node node) {
return node == null || Quad.isDefaultGraph(node) ;
}
/** Get triples with the same subject */
private Collection triplesOfSubject(Node subj) {
return RiotLib.triplesOfSubject(graph, subj) ;
}
private Iterator listSubjects() {
return GLib.listSubjects(graph) ;
}
// ---- Data access
/** Find Bnodes that can written as []
* Subject position (top level) - only used for subject position anywhere in the dataset
* Object position (any level) - only used as object once anywhere in the dataset
*/
private void findBNodesSyntax1() {
Set rejects = new HashSet<>() ; // Nodes known not to meet the requirement.
ExtendedIterator iter = find(Node.ANY, Node.ANY, Node.ANY) ;
try {
for ( ; iter.hasNext() ; ) {
Triple t = iter.next() ;
Node subj = t.getSubject() ;
Node obj = t.getObject() ;
if ( subj.isBlank() )
{
int sConn = inLinks(subj) ;
if ( sConn == 0 && containedInOneGraph(subj) )
// Not used as an object in this graph.
freeBnodes.add(subj) ;
}
if ( ! obj.isBlank() )
continue ;
if ( rejects.contains(obj) )
continue ;
int connectivity = inLinks(obj) ;
if ( connectivity == 1 && containedInOneGraph(obj) ) {
// If not used in another graph (or as graph name)
nestedObjects.add(obj) ;
}
else
// Uninteresting object connected multiple times.
rejects.add(obj) ;
}
} finally { iter.close() ; }
}
// --- Lists setup
/*
* Find all list heads and all nodes in well-formed lists. Return a
* (list head -> Elements map), list elements)
*/
private void findLists() {
List tails = triples(Node.ANY, RDF_Rest, RDF_Nil) ;
for ( Triple t : tails ) {
// Returns the elements, reversed.
Collection listElts2 = new HashSet<>() ;
Pair> p = followTailToHead(t.getSubject(), listElts2) ;
if ( p != null ) {
Node headElt = p.getLeft() ;
// Free standing/private
List elts = p.getRight() ;
long numLinks = countTriples(null, null, headElt) ;
if ( numLinks == 1 )
lists.put(headElt, elts) ;
else if ( numLinks == 0 )
// 0 connected lists
freeLists.put(headElt, elts) ;
else
// Two triples to this list.
nLinkedLists.put(headElt, elts) ;
listElts.addAll(listElts2) ;
}
}
}
// return head elt node, list of elements.
private Pair> followTailToHead(Node lastListElt, Collection listElts) {
List listCells = new ArrayList<>() ;
List eltsReversed = new ArrayList<>() ;
List acc = new ArrayList<>() ;
Node x = lastListElt ;
for ( ; ; ) {
if ( !validListElement(x, acc) ) {
if ( listCells.size() == 0 )
// No earlier valid list.
return null ;
// Fix up to previous valid list cell.
x = listCells.remove(listCells.size() - 1) ;
break ;
}
Triple t = triple1(x, RDF_First, null) ;
if ( t == null )
return null ;
eltsReversed.add(t.getObject()) ;
listCells.add(x) ;
// Try to move up the list.
List acc2 = triples(null, null, x) ;
long numRest = countTriples(null, RDF_Rest, x) ;
if ( numRest != 1 ) {
// Head of well-formed list.
// Classified by 0,1,more links later.
listCells.add(x) ;
break ;
}
// numRest == 1
int numLinks = acc2.size() ;
if ( numLinks > 1 )
// Non-list links to x
break ;
// Valid.
Triple tLink = acc2.get(0) ;
x = tLink.getSubject() ;
}
// Success.
listElts.addAll(listCells) ;
Collections.reverse(eltsReversed) ;
return Pair.create(x, eltsReversed) ;
}
/** Return the triples of the list element, or null if invalid list */
private boolean validListElement(Node x, List acc) {
Triple t1 = triple1(x, RDF_Rest, null) ; // Which we came up to get
// here :-(
if ( t1 == null )
return false ;
Triple t2 = triple1(x, RDF_First, null) ;
if ( t2 == null )
return false ;
long N = countTriples(x, null, null) ;
if ( N != 2 )
return false ;
acc.add(t1) ;
acc.add(t2) ;
return true ;
}
// ----
private void writeGraph() {
Iterator subjects = listSubjects() ;
boolean somethingWritten = writeBySubject(subjects) ;
// Write remainders
// 1 - Shared lists
somethingWritten = writeRemainingNLinkedLists(somethingWritten) ;
// 2 - Free standing lists
somethingWritten = writeRemainingFreeLists(somethingWritten) ;
// 3 - Blank nodes that are unwrittern single objects.
// System.err.println("## ## ##") ;
// printDetails("nestedObjects", nestedObjects) ;
// printDetails("nestedObjectsWritten", nestedObjectsWritten) ;
Set singleNodes = SetUtils.difference(nestedObjects, nestedObjectsWritten) ;
somethingWritten = writeRemainingNestedObjects(singleNodes, somethingWritten) ;
}
private boolean writeRemainingNLinkedLists(boolean somethingWritten) {
// Print carefully - need a label for the first cell.
// So we write out the first element of the list in triples, then
// put the remainer as a pretty list
for ( Node n : nLinkedLists.keySet() ) {
if ( somethingWritten )
out.println() ;
somethingWritten = true ;
List x = nLinkedLists.get(n) ;
writeNode(n) ;
write_S_P_Gap();
out.pad() ;
writeNode(RDF_First) ;
print(" ") ;
writeNode(x.get(0)) ;
print(" ;") ;
println() ;
writeNode(RDF_Rest) ;
print(" ") ;
x = x.subList(1, x.size()) ;
writeList(x) ;
print(" .") ;
out.decIndent(INDENT_PREDICATE) ;
println() ;
}
return somethingWritten ;
}
// Write free standing lists - ones where the head is not an object of
// some other triple. Turtle does not allow free standing (... ) .
// so write as a predicateObjectList for one element.
private boolean writeRemainingFreeLists(boolean somethingWritten) {
for ( Node n : freeLists.keySet() ) {
if ( somethingWritten )
out.println() ;
somethingWritten = true ;
List x = freeLists.get(n) ;
// Print first element for the [ ... ]
out.print("[ ") ;
writeNode(RDF_First) ;
print(" ") ;
writeNode(x.get(0)) ;
print(" ; ") ;
writeNode(RDF_Rest) ;
print(" ") ;
x = x.subList(1, x.size()) ;
// Print remainder.
writeList(x) ;
out.println(" ] .") ;
}
return somethingWritten ;
}
// Write any left over nested objects
// These come from blank node cycles : _:a _:b . _b:
_:a .
// Also from from blank node cycles + tail: _:a
_:b . _:a
"" . _b:
_:a .
private boolean writeRemainingNestedObjects(Set objects, boolean somethingWritten) {
for ( Node n : objects ) {
if ( somethingWritten )
out.println() ;
somethingWritten = true ;
Triple t = triple1(null, null, n) ;
if ( t == null )
throw new InternalErrorException("Expected exactly one triple") ;
Node subj = t.getSubject() ;
boolean b = allowDeepPretty ;
try {
allowDeepPretty = false;
Collection triples = triples(subj, null, null) ;
writeCluster(subj, triples);
} finally { allowDeepPretty = b ; }
}
return somethingWritten ;
}
// Write triples, flat and simply.
// Reset the state variables so "isPretty" return false.
private void writeTriples(Node subj, Iterator iter) {
allowDeepPretty = false;
writeCluster(subj, Iter.toList(iter));
}
// return true if did write something.
private boolean writeBySubject(Iterator subjects) {
boolean first = true ;
for ( ; subjects.hasNext() ; ) {
Node subj = subjects.next() ;
if ( nestedObjects.contains(subj) )
continue ;
if ( listElts.contains(subj) )
continue ;
if ( !first )
out.println() ;
first = false ;
if ( freeBnodes.contains(subj) ) {
// Top level: write in "[....]" on "[] :p" form.
writeNestedObjectTopLevel(subj) ;
continue ;
}
Collection cluster = triplesOfSubject(subj) ;
writeCluster(subj, cluster) ;
}
return !first ;
}
// A Cluster is a collection of triples with the same subject.
private void writeCluster(Node subject, Collection cluster) {
if ( cluster.isEmpty() )
return ;
writeNode(subject) ;
writeClusterPredicateObjectList(INDENT_PREDICATE, cluster) ;
}
// Write the PredicateObjectList for a subject already output.
// The subject may have been a "[]" or a URI - the indentation is passed in.
private void writeClusterPredicateObjectList(int indent, Collection cluster) {
write_S_P_Gap() ;
out.incIndent(indent) ;
out.pad() ;
writePredicateObjectList(cluster) ;
out.decIndent(indent) ;
print(" .") ;
println() ;
}
// Writing predicate-object lists.
// We group the cluster by predicate and within each group
// we print:
// literals, then simple objects, then pretty objects
private void writePredicateObjectList(Collection cluster) {
Map> pGroups = groupByPredicates(cluster) ;
Collection predicates = pGroups.keySet() ;
// Find longest predicate URI
int predicateMaxWidth = RiotLib.calcWidth(prefixMap, baseURI, predicates, MIN_PREDICATE, LONG_PREDICATE) ;
boolean first = true ;
if ( !OBJECT_LISTS ) {
for ( Node p : predicates ) {
for ( Node o : pGroups.get(p) ) {
writePredicateObject(p, o, predicateMaxWidth, first) ;
first = false ;
}
}
return ;
}
for ( Node p : predicates ) {
// Literals in the group
List rdfLiterals = new ArrayList<>() ;
// Non-literals, printed
List rdfSimpleNodes = new ArrayList<>() ;
// Non-literals, printed (), or []-embedded
List rdfComplexNodes = new ArrayList<>() ;
for ( Node o : pGroups.get(p) ) {
if ( o.isLiteral() ) {
rdfLiterals.add(o) ;
continue ;
}
if ( isPrettyNode(o) ) {
rdfComplexNodes.add(o) ;
continue ;
}
rdfSimpleNodes.add(o) ;
}
if ( ! rdfLiterals.isEmpty() ) {
writePredicateObjectList(p, rdfLiterals, predicateMaxWidth, first) ;
first = false ;
}
if ( ! rdfSimpleNodes.isEmpty() ) {
writePredicateObjectList(p, rdfSimpleNodes, predicateMaxWidth, first) ;
first = false ;
}
for ( Node o : rdfComplexNodes ) {
writePredicateObject(p, o, predicateMaxWidth, first) ;
first = false ;
}
}
}
private void writePredicateObject(Node p, Node obj, int predicateMaxWidth, boolean first) {
writePredicate(p, predicateMaxWidth, first) ;
out.incIndent(INDENT_OBJECT) ;
writeNodePretty(obj) ;
out.decIndent(INDENT_OBJECT) ;
}
private void writePredicateObjectList(Node p, List objects, int predicateMaxWidth, boolean first) {
writePredicate(p, predicateMaxWidth, first) ;
out.incIndent(INDENT_OBJECT) ;
boolean lastObjectMultiLine = false ;
boolean firstObject = true ;
for ( Node o : objects ) {
if ( !firstObject ) {
if ( out.getCurrentOffset() > 0 )
out.print(" , ") ;
else
// Before the current indent, due to a multiline literal being written raw.
// We will pad spaces to indent on output spaces. Don't add a first " "
out.print(", ") ;
}
else
firstObject = false ;
int row1 = out.getRow() ;
writeNode(o) ;
int row2 = out.getRow();
lastObjectMultiLine = (row2 > row1) ;
}
out.decIndent(INDENT_OBJECT) ;
}
/** Write a predicate - jump to next line if deemed long */
private void writePredicate(Node p, int predicateMaxWidth, boolean first) {
if ( ! first ) {
print(" ;") ;
println() ;
}
int colPredicateStart = out.getAbsoluteIndent() ;
if ( !prefixMap.contains(rdfNS) && RDF_type.equals(p) )
print("a") ;
else
writeNode(p) ;
int colPredicateFinish = out.getCol() ;
int wPredicate = (colPredicateFinish - colPredicateStart) ;
if ( wPredicate > LONG_PREDICATE )
println() ;
else {
out.pad(predicateMaxWidth) ;
// out.print(' ', predicateMaxWidth-wPredicate) ;
gap(GAP_P_O) ;
}
}
private Map> groupByPredicates(Collection cluster) {
SortedMap> x = new TreeMap<>(compPredicates) ;
for ( Triple t : cluster ) {
Node p = t.getPredicate() ;
if ( !x.containsKey(p) )
x.put(p, new ArrayList()) ;
x.get(p).add(t.getObject()) ;
}
return x ;
}
// Compact if one triple, or one predicate and several non-pretty objects.
private boolean isCompact(Collection cluster) {
Node predicate = null;
for ( Triple t : cluster ) {
Node p = t.getPredicate() ;
Node o = t.getObject();
if ( isPrettyNode(o) )
return false;
if ( predicate != null ) {
if ( ! predicate.equals(p))
// 2+ different predicates.
return false ;
} else
predicate = p;
}
return true;
}
// [ :p "abc" ] . or [] : "abc" .
private void writeNestedObjectTopLevel(Node subject) {
if ( true ) {
writeNestedObject(subject) ;
out.println(" .") ;
} else {
// Alternative.
Collection cluster = triplesOfSubject(subject) ;
print("[]") ;
writeClusterPredicateObjectList(0, cluster) ;
}
}
private void writeNestedObject(Node node) {
Collection x = triplesOfSubject(node) ;
if ( x.isEmpty() ) {
print("[] ") ;
return ;
}
if ( isCompact(x) ) {
print("[ ") ;
out.incIndent(2) ;
writePredicateObjectList(x) ;
out.decIndent(2) ;
print(" ]") ;
return ;
}
int indent0 = out.getAbsoluteIndent() ;
int here = out.getCol() ;
out.setAbsoluteIndent(here) ;
print("[ ") ;
out.incIndent(2) ;
writePredicateObjectList(x) ;
out.decIndent(2) ;
if ( true ) {
println() ; // Newline for "]"
print("]") ;
} else { // Compact
print(" ]") ;
}
out.setAbsoluteIndent(indent0) ;
}
// Write a list
private void writeList(List elts) {
if ( elts.size() == 0 ) {
out.print("()") ;
return ;
}
if ( false ) {
out.print("(") ;
for ( Node n : elts ) {
out.print(" ") ;
writeNodePretty(n) ;
}
out.print(" )") ;
}
if ( true ) {
// "fresh line mode" means printed one on new line
// Multi line items are ones that can be multiple lines. Non-literals.
// Was the previous row a multiLine?
boolean lastItemFreshLine = false ;
// Have there been any items that causes "fresh line" mode?
boolean multiLineAny = false ;
boolean first = true ;
// Where we started.
int originalIndent = out.getAbsoluteIndent() ;
// Rebase indent here.
int x = out.getCol() ;
out.setAbsoluteIndent(x);
out.print("(") ;
out.incIndent(2);
for ( Node n : elts ) {
// Print this item on a fresh line? (still to check: first line)
boolean thisItemFreshLine = /* multiLineAny | */ n.isBlank() ;
// Special case List in List.
// Start on this line if last item was on this line.
if ( lists.containsKey(n) )
thisItemFreshLine = lastItemFreshLine ;
// Starting point.
if ( ! first ) {
if ( lastItemFreshLine | thisItemFreshLine )
out.println() ;
else
out.print(" ") ;
}
first = false ;
//Literals with newlines: int x1 = out.getRow() ;
// Adds INDENT_OBJECT even for a [ one triple ]
// Special case [ one triple ]??
writeNodePretty(n) ;
//Literals with newlines:int x2 = out.getRow() ;
//Literals with newlines: boolean multiLineAnyway = ( x1 != x2 ) ;
lastItemFreshLine = thisItemFreshLine ;
multiLineAny = multiLineAny | thisItemFreshLine ;
}
if ( multiLineAny )
out.println() ;
else
out.print(" ") ;
out.decIndent(2);
out.setAbsoluteIndent(x);
out.print(")") ;
out.setAbsoluteIndent(originalIndent) ;
}
}
private boolean isPrettyNode(Node n) {
// Maybe ought to be the same test as writePredicateObjectList
// Order matters? - one connected objects may include list elements.
if ( allowDeepPretty ) {
if ( lists.containsKey(n) )
return true ;
if ( nestedObjects.contains(n) )
return true ;
}
if ( RDF_Nil.equals(n) )
return true ;
return false ;
}
// --> write S or O??
private void writeNodePretty(Node obj) {
// Assumes "isPrettyNode" is true.
// Order matters? - one connected objects may include list elements.
if ( lists.containsKey(obj) )
writeList(lists.get(obj)) ;
else if ( nestedObjects.contains(obj) )
writeNestedObject(obj) ;
else if ( RDF_Nil.equals(obj) )
out.print("()") ;
else
writeNode(obj) ;
if ( nestedObjects.contains(obj) )
nestedObjectsWritten.add(obj) ;
}
// Order of properties.
// rdf:type ("a")
// RDF and RDFS
// Other.
// Sorted by URI.
private void write_S_P_Gap() {
if ( out.getCol() > LONG_SUBJECT )
out.println() ;
else
gap(GAP_S_P) ;
}
}
// Order of properties.
// rdf:type ("a")
// RDF and RDFS
// Other.
// Sor0ted by URI.
private static int classification(Node p) {
if ( p.equals(RDF_type) )
return 0 ;
if ( p.getURI().startsWith(RDF.getURI()) || p.getURI().startsWith(RDFS.getURI()) )
return 1 ;
return 2 ;
}
private static Comparator compPredicates = (t1,t2) -> {
int class1 = classification(t1) ;
int class2 = classification(t2) ;
if ( class1 != class2 )
return Integer.compare(class1, class2) ;
String p1 = t1.getURI() ;
String p2 = t2.getURI() ;
return p1.compareTo(p2) ;
};
protected final void writeNode(Node node) {
nodeFmt.format(out, node) ;
}
private void print(String x) {
out.print(x) ;
}
private void gap(int gap) {
out.print(' ', gap) ;
}
// flush aggressively (debugging)
private void println() {
out.println() ;
// out.flush() ;
}
}