1 files changed, 58 insertions, 0 deletions
diff --git a/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/NAry.java b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/NAry.java
new file mode 100644
index 000000000..b010c5be6
--- /dev/null
+++ b/bundles/org.eclipse.equinox.p2.ql/src/org/eclipse/equinox/internal/p2/ql/NAry.java
@@ -0,0 +1,58 @@
+/*******************************************************************************
+ * Copyright (c) 2009 Cloudsmith Inc. and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Cloudsmith Inc. - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.equinox.internal.p2.ql;
+
+/**
+ * The abstract baseclass for all N-ary expressions
+ *
+ */
+abstract class NAry extends Expression {
+	static Expression[] assertLength(Expression[] operands, int length, String operand) {
+		if (operands == null)
+			operands = emptyArray;
+		if (operands.length < length)
+			throw new IllegalArgumentException("Not enough operands for " + operand); //$NON-NLS-1$
+		return operands;
+	}
+
+	final Expression[] operands;
+
+	NAry(Expression[] operands) {
+		this.operands = operands;
+	}
+
+	public boolean accept(Visitor visitor) {
+		if (super.accept(visitor))
+			for (int idx = 0; idx < operands.length; ++idx)
+				if (!operands[idx].accept(visitor))
+					return false;
+		return true;
+	}
+
+	public void toString(StringBuffer bld) {
+		appendOperand(bld, operands[0], getPriority());
+		for (int idx = 1; idx < operands.length; ++idx) {
+			bld.append(' ');
+			bld.append(getOperator());
+			bld.append(' ');
+			appendOperand(bld, operands[idx], getPriority());
+		}
+	}
+
+	int countReferenceToEverything() {
+		int count = 0;
+		for (int idx = 0; count < 2 && idx < operands.length; ++idx)
+			count += operands[idx].countReferenceToEverything();
+		return count;
+	}
+
+	abstract String getOperator();
+}