JavacErrorDetail.java
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.jasper.compiler;
import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import org.apache.jasper.JspCompilationContext;
import org.apache.tomcat.Jar;
/**
* Class providing details about a javac compilation error.
*
* @author Jan Luehe
* @author Kin-man Chung
*/
public class JavacErrorDetail {
private final String javaFileName;
private final int javaLineNum;
private String jspFileName;
private int jspBeginLineNum;
private final StringBuilder errMsg;
private String jspExtract = null;
/**
* Constructor.
*
* @param javaFileName The name of the Java file in which the
* compilation error occurred
* @param javaLineNum The compilation error line number
* @param errMsg The compilation error message
*/
public JavacErrorDetail(String javaFileName,
int javaLineNum,
StringBuilder errMsg) {
this(javaFileName, javaLineNum, null, -1, errMsg, null);
}
/**
* Constructor.
*
* @param javaFileName The name of the Java file in which the
* compilation error occurred
* @param javaLineNum The compilation error line number
* @param jspFileName The name of the JSP file from which the Java source
* file was generated
* @param jspBeginLineNum The start line number of the JSP element
* responsible for the compilation error
* @param errMsg The compilation error message
* @param ctxt The compilation context
*/
public JavacErrorDetail(String javaFileName,
int javaLineNum,
String jspFileName,
int jspBeginLineNum,
StringBuilder errMsg,
JspCompilationContext ctxt) {
this.javaFileName = javaFileName;
this.javaLineNum = javaLineNum;
this.errMsg = errMsg;
this.jspFileName = jspFileName;
// Note: this.jspBeginLineNum is set at the end of this method as it may
// be modified (corrected) during the execution of this method
if (jspBeginLineNum > 0 && ctxt != null) {
InputStream is = null;
try {
Jar tagJar = ctxt.getTagFileJar();
if (tagJar != null) {
// Strip leading '/'
String entryName = jspFileName.substring(1);
is = tagJar.getInputStream(entryName);
this.jspFileName = tagJar.getURL(entryName);
} else {
is = ctxt.getResourceAsStream(jspFileName);
}
// Read both files in, so we can inspect them
String[] jspLines = readFile(is);
try (FileInputStream fis = new FileInputStream(ctxt.getServletJavaFileName())) {
String[] javaLines = readFile(fis);
if (jspLines.length < jspBeginLineNum) {
// Avoid ArrayIndexOutOfBoundsException
// Probably bug 48498 but could be some other cause
jspExtract = Localizer.getMessage("jsp.error.bug48498");
return;
}
// If the line contains the opening of a multi-line scriptlet
// block, then the JSP line number we got back is probably
// faulty. Scan forward to match the java line...
if (jspLines[jspBeginLineNum-1].lastIndexOf("<%") >
jspLines[jspBeginLineNum-1].lastIndexOf("%>")) {
String javaLine = javaLines[javaLineNum-1].trim();
for (int i=jspBeginLineNum-1; i<jspLines.length; i++) {
if (jspLines[i].contains(javaLine)) {
// Update jsp line number
jspBeginLineNum = i+1;
break;
}
}
}
// copy out a fragment of JSP to display to the user
StringBuilder fragment = new StringBuilder(1024);
int startIndex = Math.max(0, jspBeginLineNum-1-3);
int endIndex = Math.min(
jspLines.length-1, jspBeginLineNum-1+3);
for (int i=startIndex;i<=endIndex; ++i) {
fragment.append(i+1);
fragment.append(": ");
fragment.append(jspLines[i]);
fragment.append(System.lineSeparator());
}
jspExtract = fragment.toString();
}
} catch (IOException ioe) {
// Can't read files - ignore
} finally {
if (is != null) {
try {
is.close();
} catch (IOException ignore) {
// Ignore
}
}
}
}
this.jspBeginLineNum = jspBeginLineNum;
}
/**
* Gets the name of the Java source file in which the compilation error
* occurred.
*
* @return Java source file name
*/
public String getJavaFileName() {
return this.javaFileName;
}
/**
* Gets the compilation error line number.
*
* @return Compilation error line number
*/
public int getJavaLineNumber() {
return this.javaLineNum;
}
/**
* Gets the name of the JSP file from which the Java source file was
* generated.
*
* @return JSP file from which the Java source file was generated.
*/
public String getJspFileName() {
return this.jspFileName;
}
/**
* Gets the start line number (in the JSP file) of the JSP element
* responsible for the compilation error.
*
* @return Start line number of the JSP element responsible for the
* compilation error
*/
public int getJspBeginLineNumber() {
return this.jspBeginLineNum;
}
/**
* Gets the compilation error message.
*
* @return Compilation error message
*/
public String getErrorMessage() {
return this.errMsg.toString();
}
/**
* Gets the extract of the JSP that corresponds to this message.
*
* @return Extract of JSP where error occurred
*/
public String getJspExtract() {
return this.jspExtract;
}
/**
* Reads a text file from an input stream into a String[]. Used to read in
* the JSP and generated Java file when generating error messages.
*/
private String[] readFile(InputStream s) throws IOException {
BufferedReader reader = new BufferedReader(new InputStreamReader(s));
List<String> lines = new ArrayList<>();
String line;
while ( (line = reader.readLine()) != null ) {
lines.add(line);
}
return lines.toArray(new String[0]);
}
}