这里提供下Tomcat9最简单运行源码的实现
1.去官网下载tomcat源码
2.新建pom.xml文件,与webapps,conf等文件夹平级存放,增加一些缺少的jar包(这些其实可以自己多运行几次试出来缺哪些jar包),插件的作用是不用每次刷新maven的jar包都需要调整java版本号,不会改版本号的可以看{% post_link IDEA修改java版本号 IDEA修改java版本号 %}
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0modelVersion>
<groupId>apacheTomcat9groupId>
<artifactId>apacheTomcat9artifactId>
<version>0.0.1-SNAPSHOTversion>
<name>apacheTomcat9name>
<description>Demo project for Spring Bootdescription>
<dependencies>
<dependency>
<groupId>org.apache.antgroupId>
<artifactId>antartifactId>
<version>1.10.5version>
dependency>
<dependency>
<groupId>javax.xmlgroupId>
<artifactId>jaxrpc-apiartifactId>
<version>1.1version>
dependency>
<dependency>
<groupId>wsdl4jgroupId>
<artifactId>wsdl4jartifactId>
<version>1.6.2version>
dependency>
<dependency>
<groupId>org.eclipse.jdtgroupId>
<artifactId>coreartifactId>
<version>3.1.1version>
dependency>
dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.pluginsgroupId>
<artifactId>maven-compiler-pluginartifactId>
<version>2.3.2version>
<configuration>
<source>1.8source>
<target>1.8target>
configuration>
plugin>
plugins>
build>
project>
3.删除test文件夹(因为有一些依赖我们没有引入,导致报错,test是测试用的demo不重要,可以直接删),删除webapps文件夹下的内容,放入自己打包好的war包(就是自己建的servlet项目打包出来的jar)
4.创建入口
5.修改JDTCompiler文件内容(报错的地方直接仿照前面的手动改成字符串就可以,tomcat8的源码似乎不会出现这种问题,如果懒得自己改的话我在文章最末尾贴了整个类的代码,可以自行复制)
ps:JDTCompiler修改后的文件
package org.apache.jasper.compiler;
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.StringTokenizer;
import org.apache.jasper.JasperException;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
import org.eclipse.jdt.core.compiler.IProblem;
import org.eclipse.jdt.internal.compiler.ClassFile;
import org.eclipse.jdt.internal.compiler.CompilationResult;
import org.eclipse.jdt.internal.compiler.Compiler;
import org.eclipse.jdt.internal.compiler.DefaultErrorHandlingPolicies;
import org.eclipse.jdt.internal.compiler.ICompilerRequestor;
import org.eclipse.jdt.internal.compiler.IErrorHandlingPolicy;
import org.eclipse.jdt.internal.compiler.IProblemFactory;
import org.eclipse.jdt.internal.compiler.classfmt.ClassFileReader;
import org.eclipse.jdt.internal.compiler.env.ICompilationUnit;
import org.eclipse.jdt.internal.compiler.env.INameEnvironment;
import org.eclipse.jdt.internal.compiler.env.NameEnvironmentAnswer;
import org.eclipse.jdt.internal.compiler.impl.CompilerOptions;
import org.eclipse.jdt.internal.compiler.problem.DefaultProblemFactory;
/**
* JDT class compiler. This compiler will load source dependencies from the
* context classloader, reducing dramatically disk access during
* the compilation process.
*
* Based on code from Cocoon2.
*
* @author Remy Maucherat
*/
public class JDTCompiler extends org.apache.jasper.compiler.Compiler {
private final Log log = LogFactory.getLog(JDTCompiler.class); // must not be static
/**
* Compile the servlet from .java file to .class file
*/
@Override
protected void generateClass(Map<String,SmapStratum> smaps)
throws FileNotFoundException, JasperException, Exception {
long t1 = 0;
if (log.isDebugEnabled()) {
t1 = System.currentTimeMillis();
}
final String sourceFile = ctxt.getServletJavaFileName();
final String outputDir = ctxt.getOptions().getScratchDir().getAbsolutePath();
String packageName = ctxt.getServletPackageName();
final String targetClassName =
((packageName.length() != 0) ? (packageName + ".") : "")
+ ctxt.getServletClassName();
final ClassLoader classLoader = ctxt.getJspLoader();
String[] fileNames = new String[] {sourceFile};
String[] classNames = new String[] {targetClassName};
final List<JavacErrorDetail> problemList = new ArrayList<>();
class CompilationUnit implements ICompilationUnit {
private final String className;
private final String sourceFile;
CompilationUnit(String sourceFile, String className) {
this.className = className;
this.sourceFile = sourceFile;
}
@Override
public char[] getFileName() {
return sourceFile.toCharArray();
}
@Override
public char[] getContents() {
char[] result = null;
try (FileInputStream is = new FileInputStream(sourceFile);
InputStreamReader isr = new InputStreamReader(
is, ctxt.getOptions().getJavaEncoding());
Reader reader = new BufferedReader(isr)) {
char[] chars = new char[8192];
StringBuilder buf = new StringBuilder();
int count;
while ((count = reader.read(chars, 0,
chars.length)) > 0) {
buf.append(chars, 0, count);
}
result = new char[buf.length()];
buf.getChars(0, result.length, result, 0);
} catch (IOException e) {
log.error(Localizer.getMessage("jsp.error.compilation.source", sourceFile), e);
}
return result;
}
@Override
public char[] getMainTypeName() {
int dot = className.lastIndexOf('.');
if (dot > 0) {
return className.substring(dot + 1).toCharArray();
}
return className.toCharArray();
}
@Override
public char[][] getPackageName() {
StringTokenizer izer =
new StringTokenizer(className, ".");
char[][] result = new char[izer.countTokens()-1][];
for (int i = 0; i < result.length; i++) {
String tok = izer.nextToken();
result[i] = tok.toCharArray();
}
return result;
}
public boolean ignoreOptionalProblems() {
return false;
}
}
final INameEnvironment env = new INameEnvironment() {
@Override
public NameEnvironmentAnswer
findType(char[][] compoundTypeName) {
StringBuilder result = new StringBuilder();
for (int i = 0; i < compoundTypeName.length; i++) {
if(i > 0)
result.append('.');
result.append(compoundTypeName[i]);
}
return findType(result.toString());
}
@Override
public NameEnvironmentAnswer
findType(char[] typeName,
char[][] packageName) {
StringBuilder result = new StringBuilder();
int i=0;
for (; i < packageName.length; i++) {
if(i > 0)
result.append('.');
result.append(packageName[i]);
}
if(i > 0)
result.append('.');
result.append(typeName);
return findType(result.toString());
}
private NameEnvironmentAnswer findType(String className) {
if (className.equals(targetClassName)) {
ICompilationUnit compilationUnit =
new CompilationUnit(sourceFile, className);
return
new NameEnvironmentAnswer(compilationUnit, null);
}
String resourceName =
className.replace('.', '/') + ".class";
try (InputStream is = classLoader.getResourceAsStream(resourceName)) {
if (is != null) {
byte[] classBytes;
byte[] buf = new byte[8192];
ByteArrayOutputStream baos =
new ByteArrayOutputStream(buf.length);
int count;
while ((count = is.read(buf, 0, buf.length)) > 0) {
baos.write(buf, 0, count);
}
baos.flush();
classBytes = baos.toByteArray();
char[] fileName = className.toCharArray();
ClassFileReader classFileReader =
new ClassFileReader(classBytes, fileName,
true);
return
new NameEnvironmentAnswer(classFileReader, null);
}
} catch (IOException exc) {
log.error(Localizer.getMessage("jsp.error.compilation.dependent", className), exc);
} catch (org.eclipse.jdt.internal.compiler.classfmt.ClassFormatException exc) {
log.error(Localizer.getMessage("jsp.error.compilation.dependent", className), exc);
}
return null;
}
private boolean isPackage(String result) {
if (result.equals(targetClassName)) {
return false;
}
String resourceName = result.replace('.', '/') + ".class";
try (InputStream is =
classLoader.getResourceAsStream(resourceName)) {
return is == null;
} catch (IOException e) {
// we are here, since close on is failed. That means it was not null
return false;
}
}
@Override
public boolean isPackage(char[][] parentPackageName,
char[] packageName) {
StringBuilder result = new StringBuilder();
int i=0;
if (parentPackageName != null) {
for (; i < parentPackageName.length; i++) {
if(i > 0)
result.append('.');
result.append(parentPackageName[i]);
}
}
if (Character.isUpperCase(packageName[0])) {
if (!isPackage(result.toString())) {
return false;
}
}
if(i > 0)
result.append('.');
result.append(packageName);
return isPackage(result.toString());
}
@Override
public void cleanup() {
}
};
final IErrorHandlingPolicy policy =
DefaultErrorHandlingPolicies.proceedWithAllProblems();
final Map<String,String> settings = new HashMap<>();
settings.put(CompilerOptions.OPTION_LineNumberAttribute,
CompilerOptions.GENERATE);
settings.put(CompilerOptions.OPTION_SourceFileAttribute,
CompilerOptions.GENERATE);
settings.put(CompilerOptions.OPTION_ReportDeprecation,
CompilerOptions.IGNORE);
if (ctxt.getOptions().getJavaEncoding() != null) {
settings.put(CompilerOptions.OPTION_Encoding,
ctxt.getOptions().getJavaEncoding());
}
if (ctxt.getOptions().getClassDebugInfo()) {
settings.put(CompilerOptions.OPTION_LocalVariableAttribute,
CompilerOptions.GENERATE);
}
// Source JVM
if(ctxt.getOptions().getCompilerSourceVM() != null) {
String opt = ctxt.getOptions().getCompilerSourceVM();
if(opt.equals("1.1")) {
settings.put(CompilerOptions.OPTION_Source,
CompilerOptions.VERSION_1_1);
} else if(opt.equals("1.2")) {
settings.put(CompilerOptions.OPTION_Source,
CompilerOptions.VERSION_1_2);
} else if(opt.equals("1.3")) {
settings.put(CompilerOptions.OPTION_Source,
CompilerOptions.VERSION_1_3);
} else if(opt.equals("1.4")) {
settings.put(CompilerOptions.OPTION_Source,
CompilerOptions.VERSION_1_4);
} else if(opt.equals("1.5")) {
settings.put(CompilerOptions.OPTION_Source,
CompilerOptions.VERSION_1_5);
} else if(opt.equals("1.6")) {
settings.put(CompilerOptions.OPTION_Source,
"1.6");
} else if(opt.equals("1.7")) {
settings.put(CompilerOptions.OPTION_Source,
"1.7");
} else if(opt.equals("1.8")) {
settings.put(CompilerOptions.OPTION_Source,
"1.8");
// Version format changed from Java 9 onwards.
// Support old format that was used in EA implementation as well
} else if(opt.equals("9") || opt.equals("1.9")) {
settings.put(CompilerOptions.OPTION_Source,
"1.9");
} else if(opt.equals("10")) {
settings.put(CompilerOptions.OPTION_Source,
"10");
} else if(opt.equals("11")) {
settings.put(CompilerOptions.OPTION_Source,
"11");
} else if(opt.equals("12")) {
// Constant not available in latest ECJ version shipped with
// Tomcat. May be supported in a snapshot build.
// This is checked against the actual version below.
settings.put(CompilerOptions.OPTION_Source, "12");
} else if(opt.equals("13")) {
// Constant not available in latest ECJ version shipped with
// Tomcat. May be supported in a snapshot build.
// This is checked against the actual version below.
settings.put(CompilerOptions.OPTION_Source, "13");
} else {
log.warn(Localizer.getMessage("jsp.warning.unknown.sourceVM", opt));
settings.put(CompilerOptions.OPTION_Source,
"1.8");
}
} else {
// Default to 1.8
settings.put(CompilerOptions.OPTION_Source,
"1.8");
}
// Target JVM
if(ctxt.getOptions().getCompilerTargetVM() != null) {
String opt = ctxt.getOptions().getCompilerTargetVM();
if(opt.equals("1.1")) {
settings.put(CompilerOptions.OPTION_TargetPlatform,
CompilerOptions.VERSION_1_1);
} else if(opt.equals("1.2")) {
settings.put(CompilerOptions.OPTION_TargetPlatform,
CompilerOptions.VERSION_1_2);
} else if(opt.equals("1.3")) {
settings.put(CompilerOptions.OPTION_TargetPlatform,
CompilerOptions.VERSION_1_3);
} else if(opt.equals("1.4")) {
settings.put(CompilerOptions.OPTION_TargetPlatform,
CompilerOptions.VERSION_1_4);
} else if(opt.equals("1.5")) {
settings.put(CompilerOptions.OPTION_TargetPlatform,
CompilerOptions.VERSION_1_5);
settings.put(CompilerOptions.OPTION_Compliance,
CompilerOptions.VERSION_1_5);
} else if(opt.equals("1.6")) {
settings.put(CompilerOptions.OPTION_TargetPlatform,
"1.6");
settings.put(CompilerOptions.OPTION_Compliance,
"1.6");
} else if(opt.equals("1.7")) {
settings.put(CompilerOptions.OPTION_TargetPlatform,
"1.7");
settings.put(CompilerOptions.OPTION_Compliance,
"1.7");
} else if(opt.equals("1.8")) {
settings.put(CompilerOptions.OPTION_TargetPlatform,
"1.8");
settings.put(CompilerOptions.OPTION_Compliance,
"1.8");
// Version format changed from Java 9 onwards.
// Support old format that was used in EA implementation as well
} else if(opt.equals("9") || opt.equals("1.9")) {
settings.put(CompilerOptions.OPTION_TargetPlatform,
"1.9");
settings.put(CompilerOptions.OPTION_Compliance,
"1.9");
} else if(opt.equals("10")) {
settings.put(CompilerOptions.OPTION_TargetPlatform,
"10");
settings.put(CompilerOptions.OPTION_Compliance,
"10");
} else if(opt.equals("11")) {
settings.put(CompilerOptions.OPTION_TargetPlatform,
"11");
settings.put(CompilerOptions.OPTION_Compliance,
"11");
} else if(opt.equals("12")) {
// Constant not available in latest ECJ version shipped with
// Tomcat. May be supported in a snapshot build.
// This is checked against the actual version below.
settings.put(CompilerOptions.OPTION_TargetPlatform, "12");
settings.put(CompilerOptions.OPTION_Compliance, "12");
} else if(opt.equals("13")) {
// Constant not available in latest ECJ version shipped with
// Tomcat. May be supported in a snapshot build.
// This is checked against the actual version below.
settings.put(CompilerOptions.OPTION_TargetPlatform, "13");
settings.put(CompilerOptions.OPTION_Compliance, "13");
} else {
log.warn(Localizer.getMessage("jsp.warning.unknown.targetVM", opt));
settings.put(CompilerOptions.OPTION_TargetPlatform,
"1.8");
}
} else {
// Default to 1.8
settings.put(CompilerOptions.OPTION_TargetPlatform,
"1.8");
settings.put(CompilerOptions.OPTION_Compliance,
"1.8");
}
final IProblemFactory problemFactory =
new DefaultProblemFactory(Locale.getDefault());
final ICompilerRequestor requestor = new ICompilerRequestor() {
@Override
public void acceptResult(CompilationResult result) {
try {
if (result.hasProblems()) {
IProblem[] problems = result.getProblems();
for (int i = 0; i < problems.length; i++) {
IProblem problem = problems[i];
if (problem.isError()) {
String name =
new String(problems[i].getOriginatingFileName());
try {
problemList.add(ErrorDispatcher.createJavacError
(name, pageNodes, new StringBuilder(problem.getMessage()),
problem.getSourceLineNumber(), ctxt));
} catch (JasperException e) {
log.error(Localizer.getMessage("jsp.error.compilation.jdtProblemError"), e);
}
}
}
}
if (problemList.isEmpty()) {
ClassFile[] classFiles = result.getClassFiles();
for (int i = 0; i < classFiles.length; i++) {
ClassFile classFile = classFiles[i];
char[][] compoundName =
classFile.getCompoundName();
StringBuilder classFileName = new StringBuilder(outputDir).append('/');
for (int j = 0;
j < compoundName.length; j++) {
if(j > 0)
classFileName.append('/');
classFileName.append(compoundName[j]);
}
byte[] bytes = classFile.getBytes();
classFileName.append(".class");
try (FileOutputStream fout = new FileOutputStream(
classFileName.toString());
BufferedOutputStream bos = new BufferedOutputStream(fout)) {
bos.write(bytes);
}
}
}
} catch (IOException exc) {
log.error(Localizer.getMessage("jsp.error.compilation.jdt"), exc);
}
}
};
ICompilationUnit[] compilationUnits =
new ICompilationUnit[classNames.length];
for (int i = 0; i < compilationUnits.length; i++) {
String className = classNames[i];
compilationUnits[i] = new CompilationUnit(fileNames[i], className);
}
CompilerOptions cOptions = new CompilerOptions(settings);
// Check source/target JDK versions as the newest versions are allowed
// in Tomcat configuration but may not be supported by the ECJ version
// being used.
String requestedSource = ctxt.getOptions().getCompilerSourceVM();
if (requestedSource != null) {
String actualSource = CompilerOptions.versionFromJdkLevel(cOptions.sourceLevel);
if (!requestedSource.equals(actualSource)) {
log.warn(Localizer.getMessage("jsp.warning.unsupported.sourceVM", requestedSource, actualSource));
}
}
String requestedTarget = ctxt.getOptions().getCompilerTargetVM();
if (requestedTarget != null) {
String actualTarget = CompilerOptions.versionFromJdkLevel(cOptions.targetJDK);
if (!requestedTarget.equals(actualTarget)) {
log.warn(Localizer.getMessage("jsp.warning.unsupported.targetVM", requestedTarget, actualTarget));
}
}
cOptions.parseLiteralExpressionsAsConstants = true;
Compiler compiler = new Compiler(env,
policy,
settings,
requestor,
problemFactory);
compiler.compile(compilationUnits);
if (!ctxt.keepGenerated()) {
File javaFile = new File(ctxt.getServletJavaFileName());
if (!javaFile.delete()) {
throw new JasperException(Localizer.getMessage(
"jsp.warning.compiler.javafile.delete.fail", javaFile));
}
}
if (!problemList.isEmpty()) {
JavacErrorDetail[] jeds =
problemList.toArray(new JavacErrorDetail[0]);
errDispatcher.javacError(jeds);
}
if( log.isDebugEnabled() ) {
long t2=System.currentTimeMillis();
log.debug("Compiled " + ctxt.getServletJavaFileName() + " "
+ (t2-t1) + "ms");
}
if (ctxt.isPrototypeMode()) {
return;
}
// JSR45 Support
if (! options.isSmapSuppressed()) {
SmapUtil.installSmap(smaps);
}
}
}