CompilerUtil.md
Introduction
JDK provides JavaCompiler for dynamically compiling Java source code files, which can then be loaded by a class loader. This dynamic compilation allows Java to have the characteristics of a dynamic scripting language, and Hutool encapsulates the corresponding tools for this purpose.
Usage
First, we will package the class files and jar files that the compilation depends on:
// Depend on A, compile B and C
final File libFile = ZipUtil.zip(FileUtil.file("lib.jar"),
new String[]{"a/A.class", "a/A$1.class", "a/A$InnerClass.class"},
new InputStream[]{
FileUtil.getInputStream("test-compile/a/A.class"),
FileUtil.getInputStream("test-compile/a/A$1.class"),
FileUtil.getInputStream("test-compile/a/A$InnerClass.class")
});Start compiling:
final ClassLoader classLoader = CompilerUtil.getCompiler(null)
// The source code file to be compiled
.addSource(FileUtil.file("test-compile/b/B.java"))
// The source code string to be compiled
.addSource("c.C", FileUtil.readUtf8String("test-compile/c/C.java"))
// The libraries that the compilation depends on
.addLibrary(libFile)
.compile();Load the compiled class:
final Class<?> clazz = classLoader.loadClass("c.C");
// Instantiate object c
Object obj = ReflectUtil.newInstance(clazz);