In -depth understanding of the incremental compiler framework in the Java class library
In -depth understanding of the incremental compiler framework in the Java class library
introduction:
In Java development, the compiler is a key tool. It can convert the Java code we wrote into an executable byte code so that the program can run on the Java virtual machine.In large projects, it is time -consuming to re -compile the entire project every time you modify the code.Due to this problem, the incremental compiler framework came into being.
What is an incremental compiler framework?
The incremental compiler framework is a tool that can only compile the Java source code that can only be compiled.It only re -compiles the modified files without re -compiling the entire project.This greatly improves development efficiency and reduces the time when developers are waiting for compilation.
How does an incremental compiler framework work?
The incremental compiler framework in the Java class library is mainly composed of the following components:
1. Source Code Parser: The incremental compiler framework first analyzes the grammar structure in the code so that it can be analyzed and processed in the subsequent steps.The source code parser can analyze the source code analysis of the idiot tree or abstract syntax tree (AST). These tree structures represent the structure and semantics of the code by programming.
2. Change Detector: Change the detector will detect changes in the source code, such as modification, adding or deleting files.By comparing the code of the previous version, the incremental compiler framework can determine which files need to be re -compiled.
3. Dependency Analyzer: The incremental compiler framework needs to analyze the dependencies in the source code.When a file is modified, the dependent analyzer can determine which other files that depend on the file should be compiled.
4. Compiler: The compiler is the core component of the incremental compiler framework. It is responsible for compiling the source code into bytecode.In the process of incremental compilation, the compiler only compiles the files that have changed, so as to avoid re -compilation of the entire project.
Example:
The following is a simple example. It demonstrates how to use the incremental compiler framework in the Java class library:
import javax.tools.*;
import java.io.File;
import java.util.Arrays;
public class IncrementalCompilerExample {
public static void main(String[] args) {
JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
DiagnosticCollector<JavaFileObject> diagnosticCollector = new DiagnosticCollector<>();
StandardJavaFileManager fileManager = compiler.getStandardFileManager(diagnosticCollector, null, null);
Iterable<? extends JavaFileObject> compilationUnits = fileManager.getJavaFileObjectsFromFiles(Arrays.asList(new File("Test.java")));
JavaCompiler.CompilationTask task = compiler.getTask(null, fileManager, diagnosticCollector, null, null, compilationUnits);
task.call();
diagnosticCollector.getDiagnostics().forEach(System.out::println);
}
}
In this example, we first obtained the Java compiler and created a diagnostic collector to collect compilation errors and warning information.We then created a standard Java file manager and obtained the Java file to be compiled through the file path.Next, we created a compilation task and called it to perform the compilation operation.Finally, we print the diagnostic message to obtain the compilation results.
in conclusion:
The incremental compiler framework is a powerful tool that can improve Java development efficiency.It reduces the re -compilation time of the entire project by compiling the source code file that has only changed.Understanding and using an incremental compiler framework can enable developers to develop Java more efficiently and accelerate the construction process of code.
