Jackson is "the Java JSON library" or "the best JSON parser for Java". Or simply as "JSON for Java".

Jackson Core Source Code files are provided in the source packge (jackson-core-2.14.0-sources.jar). You can download it at Jackson Maven Website.

You can also browse Jackson Core Source Code below:

⏎ com/fasterxml/jackson/core/io/InputDecorator.java

package com.fasterxml.jackson.core.io;

import java.io.*;

/**
 * Handler class that can be used to decorate input sources.
 * Typical use is to use a filter abstraction (filtered stream,
 * reader) around original input source, and apply additional
 * processing during read operations.
 */
public abstract class InputDecorator
    implements java.io.Serializable // since 2.1
{
    private static final long serialVersionUID = 1L;
    
    /**
     * Method called by {@link com.fasterxml.jackson.core.JsonFactory} instance when
     * creating parser given an {@link InputStream}, when this decorator
     * has been registered.
     * 
     * @param ctxt IO context in use (provides access to declared encoding).
     *   NOTE: at this point context may not have all information initialized;
     *   specifically auto-detected encoding is only available once parsing starts,
     *   which may occur only after this method is called.
     * @param in Original input source
     * 
     * @return InputStream to use; either 'in' as is, or decorator
     *   version that typically delogates to 'in'
     *
     * @throws IOException if construction of {@link InputStream} fails
     */
    public abstract InputStream decorate(IOContext ctxt, InputStream in)
        throws IOException;

    /**
     * Method called by {@link com.fasterxml.jackson.core.JsonFactory} instance when
     * creating parser on given "raw" byte source.
     * Method can either construct a {@link InputStream} for reading; or return
     * null to indicate that no wrapping should occur.
     * 
     * @param ctxt IO context in use (provides access to declared encoding)
     *   NOTE: at this point context may not have all information initialized;
     *   specifically auto-detected encoding is only available once parsing starts,
     *   which may occur only after this method is called.
     * @param src Input buffer that contains contents to parse
     * @param offset Offset of the first available byte in the input buffer
     * @param length Number of bytes available in the input buffer
     * 
     * @return Either {@link InputStream} to use as input source; or null to indicate
     *   that contents are to be processed as-is by caller
     *
     * @throws IOException if construction of {@link InputStream} fails
     */
    public abstract InputStream decorate(IOContext ctxt, byte[] src, int offset, int length)
        throws IOException;

    /**
     * Method called by {@link com.fasterxml.jackson.core.JsonFactory} instance when
     * creating parser given an {@link DataInput}, when this decorator
     * has been registered.
     *<p>
     * Default implementation simply throws {@link UnsupportedOperationException}
     * 
     * @param ctxt IO context in use (provides access to declared encoding).
     *   NOTE: at this point context may not have all information initialized;
     *   specifically auto-detected encoding is only available once parsing starts,
     *   which may occur only after this method is called.
     * @param input Original input source
     * 
     * @return InputStream to use; either 'input' as is, or decorator
     *   version that typically delogates to 'input'
     *
     * @throws IOException if construction of {@link DataInput} fails
     *
     * @since 2.8
     */
    public DataInput decorate(IOContext ctxt, DataInput input)
        throws IOException {
        throw new UnsupportedOperationException();
    }

    /**
     * Method called by {@link com.fasterxml.jackson.core.JsonFactory} instance when
     * creating parser given an {@link Reader}, when this decorator
     * has been registered.
     * 
     * @param ctxt IO context in use (provides access to declared encoding)
     *   NOTE: at this point context may not have all information initialized;
     *   specifically auto-detected encoding is only available once parsing starts,
     *   which may occur only after this method is called.
     * @param r Original reader
     * 
     * @return Reader to use; either passed in argument, or something that
     *   calls it (for example, a {@link FilterReader})
     *
     * @throws IOException if construction of {@link Reader} fails
     */
    public abstract Reader decorate(IOContext ctxt, Reader r) throws IOException;
}

⏎ com/fasterxml/jackson/core/io/InputDecorator.java

Or download all of them as a single archive file:

File name: jackson-core-2.14.0-sources.jar
File size: 497693 bytes
Release date: 2022-11-05
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