package cn.platform.agent.frame.core.helper;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import java.io.*;
import java.util.ArrayList;

/**
 * <p>标题: </p>
 * <p>功能描述: </p>
 * <p>创建时间：17/4/12 </p>
 * <p>作者：SIVEN</p>
 * <p>修改历史记录：</p>
 * ============================================================<br>
 */
public class ThrowableInfoHelper {

    protected final Log logger = LogFactory.getLog(getClass());
    /**
     * =======================================================================
     * 获得操作系统中，换行字符串。如Micorsoft Windows XP专业版中换行符"\r\n"
     * =======================================================================
     */
    // Note that the line.separator property can be looked up even by applets.
    // 参考org.apache.log4j.Layout
    public final static String LINE_SEP = System.getProperty("line.separator");
    // 参考java.io.BufferedWriter
    public final static String LINE_SEP2 = (String) java.security.AccessController
            .doPrivileged(new sun.security.action.GetPropertyAction(
                    "line.separator"));

    /**
     * @param throwable 异常对象
     * @return
     * @Description:将Throwable对象的错误堆栈内容形成字符串<br> 参考
     * {@link org.apache.log4j.spi.ThrowableInformation}
     * 代码
     * @author mahh
     * @since：2014-9-30 下午02:32:51
     */
    public static String[] getThrowableStrRep(Throwable throwable) {
        if (throwable == null) {
            return new String[0];
        }
        StringWriter sw = new StringWriter();
        PrintWriter pw = new PrintWriter(sw);
        throwable.printStackTrace(pw);
        pw.flush();
        LineNumberReader reader = new LineNumberReader(new StringReader(
                sw.toString()));
        ArrayList lines = new ArrayList();
        try {
            String line = reader.readLine();
            while (line != null) {
                lines.add(line);
                line = reader.readLine();
            }
        } catch (IOException ex) {
            lines.add(ex.toString());
        }
        String[] rep = new String[lines.size()];
        lines.toArray(rep);
        return rep;
    }


    public static String getThrowableStr(Throwable throwable) {
        StringBuffer throwableStr = new StringBuffer();
        String[] errorStrArray = getThrowableStrRep(throwable);
        for (int i = 0; i < errorStrArray.length; i++) {
            throwableStr.append(errorStrArray[i]).append(LINE_SEP2);
        }
        return throwableStr.toString();
    }

    // 测试代码
    public static void main(String[] args) {
        RuntimeException e1 = new RuntimeException("aaa");
        RuntimeException e2 = new RuntimeException("e2", e1);
        RuntimeException e3 = new RuntimeException(e2);

        System.out.println("=====");
        String throwableStr = getThrowableStr(e3);
        System.out.println(throwableStr);
    }
}