MergeNestedTryStatementsIntention.java

/*
 * Copyright 2000-2015 JetBrains s.r.o.
 *
 * 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 com.siyeh.ipp.exceptions;

import com.intellij.psi.*;
import com.intellij.util.IncorrectOperationException;
import com.siyeh.ipp.base.Intention;
import com.siyeh.ipp.base.PsiElementPredicate;
import org.jetbrains.annotations.NotNull;

/**
 * @author Bas Leijdekkers
 */
public class MergeNestedTryStatementsIntention extends Intention {

  @NotNull
  @Override
  protected PsiElementPredicate getElementPredicate() {
    return new NestedTryStatementsPredicate();
  }

  @Override
  protected void processIntention(@NotNull PsiElement element) throws IncorrectOperationException {
    final PsiTryStatement tryStatement1 = (PsiTryStatement)element.getParent();
    final StringBuilder newTryStatement = new StringBuilder("try ");
    final PsiResourceList list1 = tryStatement1.getResourceList();
    int resourceCount = 0;
    if (list1 != null) {
      resourceCount = appendResources(newTryStatement, resourceCount, list1);
    }
    final PsiCodeBlock tryBlock1 = tryStatement1.getTryBlock();
    if (tryBlock1 == null) {
      return;
    }
    final PsiStatement[] statements = tryBlock1.getStatements();
    if (statements.length != 1) {
      return;
    }
    final PsiTryStatement tryStatement2 = (PsiTryStatement)statements[0];
    final PsiResourceList list2 = tryStatement2.getResourceList();
    if (list2 != null) {
      resourceCount = appendResources(newTryStatement, resourceCount, list2);
    }
    if (resourceCount > 0) {
      newTryStatement.append(')');
    }
    final PsiCodeBlock tryBlock2 = tryStatement2.getTryBlock();
    if (tryBlock2 == null) {
      return;
    }
    newTryStatement.append(tryBlock2.getText());
    final PsiCatchSection[] catchSections2 = tryStatement2.getCatchSections();
    for (PsiCatchSection section : catchSections2) {
      newTryStatement.append(section.getText());
    }
    final PsiCatchSection[] catchSections1 = tryStatement1.getCatchSections();
    for (PsiCatchSection section : catchSections1) {
      newTryStatement.append(section.getText());
    }
    final PsiElementFactory factory = JavaPsiFacade.getElementFactory(element.getProject());
    final PsiStatement newStatement = factory.createStatementFromText(newTryStatement.toString(), element);
    tryStatement1.replace(newStatement);
  }

  private static int appendResources(StringBuilder newTryStatement, int count, PsiResourceList list) {
    for (PsiResourceListElement resource : list) {
      if (count == 0) newTryStatement.append('(');
      if (count > 0) newTryStatement.append(';');
      newTryStatement.append(resource.getText());
      ++count;
    }
    return count;
  }
}