com.google.errorprone.ErrorProneError.java Source code

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Here is the source code for com.google.errorprone.ErrorProneError.java

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/*
 * Copyright 2016 Google Inc. All Rights Reserved.
 *
 * 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;

import com.google.common.base.Strings;
import com.google.common.base.Throwables;
import com.sun.tools.javac.util.DiagnosticSource;
import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
import com.sun.tools.javac.util.Log;
import javax.tools.JavaFileObject;

/**
 * Wraps an unrecoverable error that occurs during analysis with the source
 * position that triggered the crash.
 */
public class ErrorProneError extends Error {

    private final String checkName;
    private final Throwable cause;
    private final DiagnosticPosition pos;
    private final JavaFileObject source;

    public ErrorProneError(String checkName, Throwable cause, DiagnosticPosition pos, JavaFileObject source) {
        super(formatMessage(checkName, source, pos, cause), cause, /*enableSuppression=*/ true,
                /*writableStackTrace=*/ false);
        this.checkName = checkName;
        this.cause = cause;
        this.pos = pos;
        this.source = source;
    }

    public void logFatalError(Log log) {
        String version = ErrorProneVersion.loadVersionFromPom().or("unknown version");
        JavaFileObject prev = log.currentSourceFile();
        try {
            log.useSource(source);
            log.error(pos, "error.prone.crash", Throwables.getStackTraceAsString(cause), version);
        } finally {
            log.useSource(prev);
        }
    }

    private static String formatMessage(String checkName, JavaFileObject file, DiagnosticPosition pos,
            Throwable cause) {
        DiagnosticSource source = new DiagnosticSource(file, /*log=*/ null);
        int column = source.getColumnNumber(pos.getStartPosition(), /*expandTabs=*/ true);
        int line = source.getLineNumber(pos.getStartPosition());
        String snippet = source.getLine(pos.getStartPosition());
        StringBuilder sb = new StringBuilder();
        sb.append(String.format("\n%s:%d: %s: An exception was thrown by Error Prone: %s\n",
                source.getFile().getName(), line, checkName, cause.getMessage()));
        sb.append(snippet).append('\n');
        if (column > 0) {
            sb.append(Strings.repeat(" ", column - 1));
        }
        sb.append("^\n");
        return sb.toString();
    }

    public String checkName() {
        return checkName;
    }
}