在kettle作业中JavaScript脚本有时候也扮演非常重要的角色，此时我们希望有一些日志记录。下面是job中JavaScript记录日志的方式。
job的js写日志的方法。
得到日志输出实例
org.pentaho.di.core.logging.LogWriter.getInstance();
按照日志的级别输出：
public void logMinimal(String subject, String message, Object... args)
{ println(LOG_LEVEL_MINIMAL, subject, message, args) ; }
public void logBasic(String subject, String message, Object... args)
{ println(LOG_LEVEL_BASIC, subject, message, args) ; }
public void logDetailed(String subject, String message, Object... args)
{ println(LOG_LEVEL_DETAILED, subject, message, args); }
public void logDebug(String subject, String message, Object... args)
{ println(LOG_LEVEL_DEBUG, subject, message, args); }
public void logRowlevel(String subject, String message, Object... args)
{ println(LOG_LEVEL_ROWLEVEL, subject, message, args); }
public void logError(String subject, String message, Object... args)
{ println(LOG_LEVEL_ERROR, subject, message, args); }
例子：
var mpType = parent_job.getVariable("IMPTYPE");
var sStart = parent_job.getVariable("STARTTIME");
var sEnd = parent_job.getVariable("ENDTIME");
var sdf = new java.text.SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
var cal = new java.util.Calendar();
var start = sdf.parse(sStart);
cal.setTime(start);
var month1 = cal.get(cal.MONTH);
var end = sdf.parse(sEnd);
cal.setTime(end);
cal.add(Calendar.DATE, -1);
var month2 = cal.get(cal.MONTH);
var log = org.pentaho.di.core.logging.LogWriter.getInstance();
log.logMinimal("<周统计做特殊处理>", "是否跨月：startTime-->" + sStart+ "; endTime-->" + sEnd + "; startMonth-->" + month1 + ";endMonth-->" + month2, "");
if((10080 == mpType) && (month1 != month2)){
var nextMonthPrefix = parent_job.getVariable("NEXTMONTABPRE");
parent_job.setVariable("MONTHTABPRE", nextMonthPrefix);
log.logMinimal("<周统计做特殊处理>", "！！！该周跨月！！！MONTHTABPRE-->" + nextMonthPrefix + "; startMonth-->" + month1 + ";endMonth-->" + month2, "");
}
true;
