| /* |
| * 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.sparql.algebra; |
| |
| import java.util.List ; |
| |
| import org.apache.jena.sparql.algebra.op.* ; |
| |
| /** One step in the transformation process. |
| * Used with Transformer, performs a bottom-up rewrite. |
| */ |
| public class TransformCopy implements Transform |
| { |
| public static final boolean COPY_ALWAYS = true ; |
| public static final boolean COPY_ONLY_ON_CHANGE = false ; |
| private boolean alwaysCopy = false ; |
| |
| public TransformCopy() { this(COPY_ONLY_ON_CHANGE) ; } |
| public TransformCopy(boolean alwaysDuplicate) { this.alwaysCopy = alwaysDuplicate ; } |
| |
| @Override |
| public Op transform(OpTable opTable) { return xform(opTable) ; } |
| @Override |
| public Op transform(OpBGP opBGP) { return xform(opBGP) ; } |
| @Override |
| public Op transform(OpQuadPattern opQuadPattern) { return xform(opQuadPattern) ; } |
| @Override |
| public Op transform(OpQuadBlock opQuadBlock) { return xform(opQuadBlock) ; } |
| @Override |
| public Op transform(OpTriple opTriple) { return xform(opTriple) ; } |
| @Override |
| public Op transform(OpQuad opQuad) { return xform(opQuad) ; } |
| @Override |
| public Op transform(OpPath opPath) { return xform(opPath) ; } |
| @Override |
| public Op transform(OpFind opFind) { return xform(opFind) ; } |
| |
| @Override |
| public Op transform(OpProcedure opProc, Op subOp) { return xform(opProc, subOp) ; } |
| @Override |
| public Op transform(OpPropFunc opPropFunc, Op subOp) { return xform(opPropFunc, subOp) ; } |
| @Override |
| public Op transform(OpDatasetNames opDatasetNames) { return xform(opDatasetNames) ; } |
| |
| @Override |
| public Op transform(OpFilter opFilter, Op subOp) { return xform(opFilter, subOp) ; } |
| @Override |
| public Op transform(OpGraph opGraph, Op subOp) { return xform(opGraph, subOp) ; } |
| @Override |
| public Op transform(OpService opService, Op subOp) { return xform(opService, subOp) ; } |
| |
| @Override |
| public Op transform(OpAssign opAssign, Op subOp) { return xform(opAssign, subOp) ; } |
| @Override |
| public Op transform(OpExtend opExtend, Op subOp) { return xform(opExtend, subOp) ; } |
| |
| @Override |
| public Op transform(OpJoin opJoin, Op left, Op right) { return xform(opJoin, left, right) ; } |
| @Override |
| public Op transform(OpLeftJoin opLeftJoin, Op left, Op right) { return xform(opLeftJoin, left, right) ; } |
| @Override |
| public Op transform(OpDiff opDiff, Op left, Op right) { return xform(opDiff, left, right) ; } |
| @Override |
| public Op transform(OpMinus opMinus, Op left, Op right) { return xform(opMinus, left, right) ; } |
| @Override |
| public Op transform(OpUnion opUnion, Op left, Op right) { return xform(opUnion, left, right) ; } |
| @Override |
| public Op transform(OpConditional opCond, Op left, Op right) { return xform(opCond, left, right) ; } |
| |
| @Override |
| public Op transform(OpSequence opSequence, List<Op> elts) { return xform(opSequence, elts) ; } |
| @Override |
| public Op transform(OpDisjunction opDisjunction, List<Op> elts) { return xform(opDisjunction, elts) ; } |
| |
| @Override |
| public Op transform(OpExt opExt) { return xform(opExt) ; } |
| |
| @Override |
| public Op transform(OpNull opNull) { return opNull.copy() ; } |
| @Override |
| public Op transform(OpLabel opLabel, Op subOp) { return xform(opLabel, subOp) ; } |
| |
| @Override |
| public Op transform(OpList opList, Op subOp) { return xform(opList, subOp) ; } |
| @Override |
| public Op transform(OpOrder opOrder, Op subOp) { return xform(opOrder, subOp) ; } |
| @Override |
| public Op transform(OpTopN opTop, Op subOp) { return xform(opTop, subOp) ; } |
| @Override |
| public Op transform(OpProject opProject, Op subOp) { return xform(opProject, subOp) ; } |
| @Override |
| public Op transform(OpDistinct opDistinct, Op subOp) { return xform(opDistinct, subOp) ; } |
| @Override |
| public Op transform(OpReduced opReduced, Op subOp) { return xform(opReduced, subOp) ; } |
| @Override |
| public Op transform(OpSlice opSlice, Op subOp) { return xform(opSlice, subOp) ; } |
| @Override |
| public Op transform(OpGroup opGroup, Op subOp) { return xform(opGroup, subOp) ; } |
| |
| private Op xform(Op0 op) |
| { |
| if ( ! alwaysCopy ) |
| return op ; |
| return op.copy() ; |
| } |
| |
| private Op xform(Op1 op, Op subOp) |
| { |
| if ( ! alwaysCopy && op.getSubOp() == subOp ) |
| return op ; |
| return op.copy(subOp) ; |
| } |
| |
| private Op xform(Op2 op, Op left, Op right) |
| { |
| if ( ! alwaysCopy && op.getLeft() == left && op.getRight() == right ) |
| return op ; |
| return op.copy(left, right) ; |
| } |
| |
| private Op xform(OpN op, List<Op> elts) |
| { |
| // Need to do one-deep equality checking. |
| if ( ! alwaysCopy && equals1(elts, op.getElements()) ) |
| return op ; |
| return op.copy(elts) ; |
| } |
| |
| private Op xform(OpExt op) |
| { |
| try { |
| return op.apply(this); |
| } catch (Exception e) { |
| // May happen if the OpExt doesn't implement apply() |
| return op; |
| } |
| } |
| |
| private boolean equals1(List<Op> list1, List<Op> list2) |
| { |
| if ( list1.size() != list2.size() ) |
| return false ; |
| for ( int i = 0 ; i < list1.size() ; i++ ) |
| { |
| if ( list1.get(i) != list2.get(i) ) |
| return false ; |
| } |
| return true ; |
| } |
| } |