codetoanalyze.java.eradicate.ReturnNotNullable.java Source code

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Here is the source code for codetoanalyze.java.eradicate.ReturnNotNullable.java

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/*
* Copyright (c) 2013 - present Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*/

package codetoanalyze.java.eradicate;

import com.google.common.base.Optional;

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;

public class ReturnNotNullable {

    void returnvoid() {
        // No warning here.
    }

    Void returnVoid() {
        // This is OK too.
        return null;
    }

    String returnNull() {
        return null;
    }

    String returnNullable(@Nullable String s) {
        return s;
    }

    @Nonnull
    String returnNonnull() {
        return "abc";
    }

    @Nullable
    String returnNullOK() {
        return null;
    }

    @Nullable
    String returnNullableOK(@Nullable String s) {
        return s;
    }

    String throwException(@Nullable Exception e, boolean bad) throws Exception {
        if (bad) {
            throw (e); // no ERADICATE_RETURN_NOT_NULLABLE should be reported
        }
        return "OK";
    }

    @Nullable
    String redundantEq() {
        String s = returnNonnull();
        int n = s == null ? 0 : s.length();
        return s;
    }

    @Nullable
    String redundantNeq() {
        String s = returnNonnull();
        int n = s != null ? 0 : s.length();
        return s;
    }

    @Nonnull
    BufferedReader nn(BufferedReader br) {
        return br;
    }

    void tryWithResources(String path) {
        try (BufferedReader br = nn(new BufferedReader(new FileReader(path)))) {
        } // no condition redundant should be reported on this line
        catch (IOException e) {
        }
    }

    /*
    Check that orNull is modelled and RETURN_OVER_ANNOTATED is not returned.
     */
    @Nullable
    String testOptional(Optional<String> os) {
        return os.orNull();
    }

    class E extends Exception {
    }

    String return_null_in_catch() {
        try {
            throw new E();
        } catch (E e) {
            return null;
        }
    }

    String return_null_in_catch_after_throw() {
        try {
            try {
                throw new E();
            } catch (E e) {
                throw e;
            }
        } catch (E e) {
            return null;
        }
    }
}