File	Doc	Category	Size	Date	Package
LocationInfo.java	API Doc	Apache log4j 1.2.15	8334	Sat Aug 25 00:09:40 BST 2007	org.apache.log4j.spi

LocationInfo

• java.lang.Object

Fields Summary
transient String	lineNumber Caller's line number.
transient String	fileName Caller's file name.
transient String	className Caller's fully qualified class name.
transient String	methodName Caller's method name.
public String	fullInfo All available caller information, in the format fully.qualified.classname.of.caller.methodName(Filename.java:line)
private static StringWriter	sw
private static PrintWriter	pw
public static final String	NA When location information is not available the constant NA is returned. Current value of this string constant is ?.
static final long	serialVersionUID
public static final LocationInfo	NA_LOCATION_INFO NA_LOCATION_INFO is provided for compatibility with log4j 1.3.
static boolean	inVisualAge

Constructors Summary
public LocationInfo(Throwable t, String fqnOfCallingClass) Instantiate location information based on a Throwable. We expect the Throwable t, to be in the format java.lang.Throwable ... at org.apache.log4j.PatternLayout.format(PatternLayout.java:413) at org.apache.log4j.FileAppender.doAppend(FileAppender.java:183) at org.apache.log4j.Category.callAppenders(Category.java:131) at org.apache.log4j.Category.log(Category.java:512) at callers.fully.qualified.className.methodName(FileName.java:74) ... However, we can also deal with JIT compilers that "lose" the location information, especially between the parentheses. try { inVisualAge = Class.forName("com.ibm.uvm.tools.DebugSupport") != null; LogLog.debug("Detected IBM VisualAge environment."); } catch(Throwable e) { // nothing to do } if(t == null || fqnOfCallingClass == null) return; String s; // Protect against multiple access to sw. synchronized(sw) { t.printStackTrace(pw); s = sw.toString(); sw.getBuffer().setLength(0); } //System.out.println("s is ["+s+"]."); int ibegin, iend; // Given the current structure of the package, the line // containing "org.apache.log4j.Category." should be printed just // before the caller. // This method of searching may not be fastest but it's safer // than counting the stack depth which is not guaranteed to be // constant across JVM implementations. ibegin = s.lastIndexOf(fqnOfCallingClass); if(ibegin == -1) return; ibegin = s.indexOf(Layout.LINE_SEP, ibegin); if(ibegin == -1) return; ibegin+= Layout.LINE_SEP_LEN; // determine end of line iend = s.indexOf(Layout.LINE_SEP, ibegin); if(iend == -1) return; // VA has a different stack trace format which doesn't // need to skip the inital 'at' if(!inVisualAge) { // back up to first blank character ibegin = s.lastIndexOf("at ", iend); if(ibegin == -1) return; // Add 3 to skip "at "; ibegin += 3; } // everything between is the requested stack item this.fullInfo = s.substring(ibegin, iend);
public LocationInfo(String file, String classname, String method, String line) Create new instance. param file source file name param classname class name param method method param line source line number since 1.2.15 this.fileName = file; this.className = classname; this.methodName = method; this.lineNumber = line; StringBuffer buf = new StringBuffer(); appendFragment(buf, classname); buf.append("."); appendFragment(buf, method); buf.append("("); appendFragment(buf, file); buf.append(":"); appendFragment(buf, line); buf.append(")"); this.fullInfo = buf.toString();

Methods Summary
private static final void	appendFragment(java.lang.StringBuffer buf, java.lang.String fragment) Appends a location fragment to a buffer to build the full location info. param buf StringBuffer to receive content. param fragment fragment of location (class, method, file, line), if null the value of NA will be appended. since 1.2.15 if (fragment == null) { buf.append(NA); } else { buf.append(fragment); }
public java.lang.String	getClassName() Return the fully qualified class name of the caller making the logging request. if(fullInfo == null) return NA; if(className == null) { // Starting the search from '(' is safer because there is // potentially a dot between the parentheses. int iend = fullInfo.lastIndexOf('("); if(iend == -1) className = NA; else { iend =fullInfo.lastIndexOf('.", iend); // This is because a stack trace in VisualAge looks like: //java.lang.RuntimeException // java.lang.Throwable() // java.lang.Exception() // java.lang.RuntimeException() // void test.test.B.print() // void test.test.A.printIndirect() // void test.test.Run.main(java.lang.String []) int ibegin = 0; if (inVisualAge) { ibegin = fullInfo.lastIndexOf(' ", iend)+1; } if(iend == -1) className = NA; else className = this.fullInfo.substring(ibegin, iend); } } return className;
public java.lang.String	getFileName() Return the file name of the caller. This information is not always available. if(fullInfo == null) return NA; if(fileName == null) { int iend = fullInfo.lastIndexOf(':"); if(iend == -1) fileName = NA; else { int ibegin = fullInfo.lastIndexOf('(", iend - 1); fileName = this.fullInfo.substring(ibegin + 1, iend); } } return fileName;
public java.lang.String	getLineNumber() Returns the line number of the caller. This information is not always available. if(fullInfo == null) return NA; if(lineNumber == null) { int iend = fullInfo.lastIndexOf(')"); int ibegin = fullInfo.lastIndexOf(':", iend -1); if(ibegin == -1) lineNumber = NA; else lineNumber = this.fullInfo.substring(ibegin + 1, iend); } return lineNumber;
public java.lang.String	getMethodName() Returns the method name of the caller. if(fullInfo == null) return NA; if(methodName == null) { int iend = fullInfo.lastIndexOf('("); int ibegin = fullInfo.lastIndexOf('.", iend); if(ibegin == -1) methodName = NA; else methodName = this.fullInfo.substring(ibegin + 1, iend); } return methodName;