content: /*
   * Copyright 2016 HuntBugs contributors
   * 
   * Licensed 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 one.util.huntbugs.detect;
  
  import com.strobel.assembler.metadata.DynamicCallSite;
  import com.strobel.assembler.metadata.IMethodSignature;
  import com.strobel.assembler.metadata.MethodHandle;
  import com.strobel.assembler.metadata.MethodHandleType;
  import com.strobel.assembler.metadata.MethodReference;
  import com.strobel.assembler.metadata.TypeReference;
  import com.strobel.decompiler.ast.AstCode;
  import com.strobel.decompiler.ast.Expression;
  
  import one.util.huntbugs.registry.MethodContext;
  import one.util.huntbugs.registry.anno.AstNodes;
  import one.util.huntbugs.registry.anno.AstVisitor;
  import one.util.huntbugs.registry.anno.WarningDefinition;
  import one.util.huntbugs.util.Nodes;
  import one.util.huntbugs.warning.Roles;
  
  /**
   * @author Tagir Valeev
   *
   */
  @WarningDefinition(category="Correctness", name="MaxMinMethodReferenceForComparator", maxScore=90)
  public class BadMethodReferences {
      @AstVisitor(nodes=AstNodes.EXPRESSIONS, minVersion=8)
      public void visit(Expression expr, MethodContext mc) {
          if(expr.getCode() == AstCode.InvokeDynamic) {
              DynamicCallSite dcs = (DynamicCallSite)expr.getOperand();
              MethodHandle actualHandle = Nodes.getMethodHandle(dcs);
              if(actualHandle != null) {
                  IMethodSignature signature = dcs.getMethodType();
                  if(signature != null) {
                      check(actualHandle, signature.getReturnType(), mc, expr);
                  }
              }
          }
      }
  
      private void check(MethodHandle handle, TypeReference functionalInterface, MethodContext mc, Expression expr) {
          if(functionalInterface.getInternalName().equals("java/util/Comparator") && handle.getHandleType() == MethodHandleType.InvokeStatic) {
              MethodReference mr = handle.getMethod();
              if((mr.getName().equals("min") || mr.getName().equals("max")) && mr.getDeclaringType().getPackageName().equals("java.lang")) {
                  mc.report("MaxMinMethodReferenceForComparator", 0, expr, Roles.METHOD_REFERENCE.create(mr));
              }
          }
      }
  }
  