Java Expression.TRUE屬性代碼示例

public static Relation createSimpleRelation(
		ConnectedDB database, Attribute[] attributes) {
	return new RelationImpl(database, AliasMap.NO_ALIASES, Expression.TRUE, Expression.TRUE,
			Collections.<Join>emptySet(), 
			new HashSet<ProjectionSpec>(Arrays.asList(attributes)), 
			false, Collections.<OrderSpec>emptyList(), -1, -1);
}
 

public void setUp() {
	db = new DummyDB();
	projections1 = Collections.<ProjectionSpec>singleton(new Attribute(null, "table", "unique"));
	projections2 = Collections.<ProjectionSpec>singleton(new Attribute(null, "table", "not_unique"));
	unique = new RelationImpl(
			db, AliasMap.NO_ALIASES, Expression.TRUE, Expression.TRUE, 
			Collections.<Join>emptySet(), 
			projections1, true, OrderSpec.NONE, Relation.NO_LIMIT, Relation.NO_LIMIT);
	notUnique = new RelationImpl(
			db, AliasMap.NO_ALIASES, Expression.TRUE, Expression.TRUE, 
			Collections.<Join>emptySet(), 
			projections2, false, OrderSpec.NONE, Relation.NO_LIMIT, Relation.NO_LIMIT);
}
 

public void testWithPrefix() {
	RelationName original = new RelationName(null, "original");
	RelationName alias = new RelationName(null, "alias");
	AliasMap aliases = AliasMap.create1(original, alias);
	Set<ProjectionSpec> projections = new HashSet<ProjectionSpec>(Arrays.asList(new Attribute[]{
			new Attribute(original, "id"), 
			new Attribute(alias, "value")}));
	Relation rel = new RelationImpl(
			null, aliases, Expression.TRUE, Expression.TRUE, 
			Collections.<Join>emptySet(), projections, false, OrderSpec.NONE, Relation.NO_LIMIT, Relation.NO_LIMIT);
	TripleRelation t = new TripleRelation(rel, 
			new TypedNodeMaker(TypedNodeMaker.URI, new Pattern("http://example.org/original/@@[email protected]@"), true),
			new FixedNodeMaker(Node.createURI("http://example.org/property"), false),
			new TypedNodeMaker(TypedNodeMaker.PLAIN_LITERAL, new Column(new Attribute(alias, "value")), false));
	assertEquals("URI(Pattern(http://example.org/original/@@[email protected]@))", 
			t.nodeMaker(TripleRelation.SUBJECT).toString());
	assertEquals("Literal(Column(alias.value))", 
			t.nodeMaker(TripleRelation.OBJECT).toString());
	assertEquals("AliasMap(original AS alias)", 
			t.baseRelation().aliases().toString());
	NodeRelation t4 = t.withPrefix(4);
	assertEquals("URI(Pattern(http://example.org/original/@@[email protected]@))", 
			t4.nodeMaker(TripleRelation.SUBJECT).toString());
	assertEquals("Literal(Column(T4_alias.value))", 
			t4.nodeMaker(TripleRelation.OBJECT).toString());
	assertEquals("AliasMap(original AS T4_alias, original AS T4_original)", 
			t4.baseRelation().aliases().toString());
}
 

public void setUp() {
	Relation base = new RelationImpl(null, AliasMap.NO_ALIASES, 
			Expression.TRUE, Expression.TRUE, 
			Collections.<Join>emptySet(), Collections.<ProjectionSpec>emptySet(), 
			false, OrderSpec.NONE, Relation.NO_LIMIT, Relation.NO_LIMIT);
	this.withURIPatternSubject = new TripleRelation(base,
			new TypedNodeMaker(TypedNodeMaker.URI, 
					new Pattern("http://test/[email protected]@[email protected]@"), true),
			new FixedNodeMaker(RDF.type.asNode(), false),
			new FixedNodeMaker(FOAF.Person.asNode(), false));
	this.withURIPatternSubjectAndObject = new TripleRelation(base,
			new TypedNodeMaker(TypedNodeMaker.URI, 
					new Pattern("http://test/[email protected]@[email protected]@"), true),
			new FixedNodeMaker(FOAF.knows.asNode(), false),
			new TypedNodeMaker(TypedNodeMaker.URI, 
					new Pattern("http://test/[email protected]@[email protected]@"), true));
	this.withURIColumnSubject = new TripleRelation(base,
			new TypedNodeMaker(TypedNodeMaker.URI, 
					new Column(new Attribute(null, "employees", "homepage")), false),
			new FixedNodeMaker(RDF.type.asNode(), false),
			new FixedNodeMaker(FOAF.Document.asNode(), false));
	this.withURIPatternSubjectAndURIColumnObject = new TripleRelation(base,
			new TypedNodeMaker(TypedNodeMaker.URI, 
					new Pattern("http://test/[email protected]@[email protected]@"), true),
			new FixedNodeMaker(FOAF.homepage.asNode(), false),
			new TypedNodeMaker(TypedNodeMaker.URI, 
					new Column(new Attribute(null, "employees", "homepage")), false));
	this.employeeChecker = new URIMakerRule().createRuleChecker(
			Node.createURI("http://test/person1"));
	this.foobarChecker = new URIMakerRule().createRuleChecker(
			Node.createURI("http://test/foobar"));
}
 

public Expression notNullExpression(ConnectedDB db, AliasMap aliases) {
	if (db.isNullable(aliases.originalOf(this))) {
		return NotNull.create(new AttributeExpr(this));
	}
	return Expression.TRUE;
}
 

public Expression valueExpression(String value) {
	return this.value.equals(value) ? Expression.TRUE : Expression.FALSE;
}
 

@Override
public Expression getRowNumLimitAsExpression(int limit) {
	if (limit == Database.NO_LIMIT) return Expression.TRUE;
	return SQLExpression.create("ROWNUM <= " + limit);
}
 

public Expression getRowNumLimitAsExpression(int limit) {
	return Expression.TRUE;
}
 

public Expression condition() { return Expression.TRUE; } 

public Expression softCondition() { return Expression.TRUE; }