/*
 * Copyright 2018 The Error Prone Authors.
 *
 * 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.google.errorprone.bugpatterns;

import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
import static com.google.errorprone.matchers.Description.NO_MATCH;
import static com.google.errorprone.matchers.Matchers.expressionStatement;
import static com.google.errorprone.matchers.method.MethodMatchers.instanceMethod;

import com.google.common.collect.Iterables;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.bugpatterns.BugChecker.CatchTreeMatcher;
import com.google.errorprone.matchers.Description;
import com.google.errorprone.matchers.Matcher;
import com.sun.source.tree.CatchTree;
import com.sun.source.tree.StatementTree;
import java.util.List;

/** A {@link BugChecker}; see the associated {@link BugPattern} annotation for details. */
@BugPattern(
    name = "CatchAndPrintStackTrace",
    summary =
        "Logging or rethrowing exceptions should usually be preferred to catching and calling"
            + " printStackTrace",
    severity = WARNING)
public class CatchAndPrintStackTrace extends BugChecker implements CatchTreeMatcher {

  private static final Matcher<StatementTree> MATCHER =
      expressionStatement(
          instanceMethod().onDescendantOf("java.lang.Throwable").named("printStackTrace"));

  @Override
  public Description matchCatch(CatchTree tree, VisitorState state) {
    List<? extends StatementTree> statements = tree.getBlock().getStatements();
    if (statements.size() != 1) {
      return NO_MATCH;
    }
    StatementTree statement = Iterables.getOnlyElement(statements);
    if (!MATCHER.matches(statement, state)) {
      return NO_MATCH;
    }
    return describeMatch(statement);
  }
}

@@ -858,16 +858,97 @@
 tement;%0A
+import static com.google.errorprone.matchers.Matchers.matchSingleStatementBlock;%0A
 import s
@@ -1346,21 +1346,21 @@
 ce.tree.
-Catch
+Block
 Tree;%0Aim
@@ -1388,44 +1388,17 @@
 ree.
-StatementTree;%0Aimport java.util.List
+CatchTree
 ;%0A%0A/
@@ -1823,25 +1823,21 @@
 Matcher%3C
-Statement
+Block
 Tree%3E MA
@@ -1844,16 +1844,53 @@
 TCHER =%0A
+      matchSingleStatementBlock(%0A    
       ex
@@ -1918,16 +1918,20 @@
         
+  
+  
 instance
@@ -2002,16 +2002,17 @@
 Trace%22))
+)
 ;%0A%0A  @Ov
@@ -2096,325 +2096,167 @@
     
-List%3C? extends StatementTree%3E statements = tree.getBlock().getStatements();%0A    if (statements.size() != 1) %7B%0A      return NO_MATCH;%0A    %7D%0A    StatementTree statement = Iterables.getOnlyElement(statements);%0A    if (!MATCHER.matches(statement, state)) %7B%0A      return NO_MATCH;%0A    %7D%0A    return describeMatch(statement)
+if (MATCHER.matches(tree.getBlock(), state)) %7B%0A      return describeMatch(Iterables.getOnlyElement(tree.getBlock().getStatements()));%0A    %7D%0A    return NO_MATCH
 ;%0A  

Simplify CatchAndPrintStackTrace using matchSingleStatementBlock matcher