Unable to execute dex: method ID not in [0, 0xffff]: 65536

/*
 * Direct-mapped "header_item" struct.
 */
struct DexHeader {
    u1  magic[8];
    u4  checksum;
    u1  signature[kSHA1DigestLen];
    u4  fileSize;
    u4  headerSize;
    u4  endianTag;
    u4  linkSize;
    u4  linkOff;
    u4  mapOff;
    u4  stringIdsSize;
    u4  stringIdsOff;
    u4  typeIdsSize;
    u4  typeIdsOff;
    u4  protoIdsSize;
    u4  protoIdsOff;
    u4  fieldIdsSize;
    u4  fieldIdsOff;
    u4  methodIdsSize; // 这里存放了方法字段索引的大小，methodIdsSize的类型为u4
    u4  methodIdsOff;
    u4  classDefsSize;
    u4  classDefsOff;
    u4  dataSize;
    u4  dataOff;
};

/*
 * These match the definitions in the VM specification.
 */
typedef uint8_t             u1;
typedef uint16_t            u2;
typedef uint32_t            u4;
typedef uint64_t            u8;
typedef int8_t              s1;
typedef int16_t             s2;
typedef int32_t             s4;
typedef int64_t             s8;

/**
 * Combine two dex files into one.
  */
public final class DexMerger {

    private void mergeMethodIds() {
        new IdMerger<MethodId>(idsDefsOut) {
            @Override TableOfContents.Section getSection(TableOfContents tableOfContents) {
                return tableOfContents.methodIds;
            }

            @Override MethodId read(Dex.Section in, IndexMap indexMap, int index) {
                return indexMap.adjust(in.readMethodId());
            }

            @Override void updateIndex(int offset, IndexMap indexMap, int oldIndex, int newIndex) {
                if (newIndex < 0 || newIndex > 0xffff) {
                    throw new DexIndexOverflowException(
                            "method ID not in [0, 0xffff]: " + newIndex);
                }
                indexMap.methodIds[oldIndex] = (short) newIndex;
            }

            @Override void write(MethodId methodId) {
                methodId.writeTo(idsDefsOut);
            }
        }.mergeSorted();
    }
}

/**
 * Maps the index offsets from one dex file to those in another. For example, if
 * you have string #5 in the old dex file, its position in the new dex file is
 * {@code strings[5]}.
 */
public final class IndexMap {
    private final Dex target;
    public final int[] stringIds;
    public final short[] typeIds;
    public final short[] protoIds;
    public final short[] fieldIds;
    public final short[] methodIds;

    // ... ...
}

// 源码目录：dalvik/dx
// Main.java
-> main() -> run() -> runMonoDex()(或者runMultiDex()) -> writeDex()
// DexFile
-> toDex() -> toDex0()
// MethodIdsSection extends MemberIdsSection extends UniformItemSection extends  Section
-> prepare() -> prepare0() -> orderItems() -> getTooManyMembersMessage()
// Main.java
-> getTooManyIdsErrorMessage()

package com.android.dx.dex.file;

import com.android.dex.DexException;
import com.android.dex.DexFormat;
import com.android.dex.DexIndexOverflowException;
import com.android.dx.command.dexer.Main;

import java.util.Formatter;
import java.util.Map;
import java.util.TreeMap;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * Member (field or method) refs list section of a {@code .dex} file.
 */
public abstract class MemberIdsSection extends UniformItemSection {

    /**
     * Constructs an instance. The file offset is initially unknown.
     *
     * @param name {@code null-ok;} the name of this instance, for annotation
     * purposes
     * @param file {@code non-null;} file that this instance is part of
     */
    public MemberIdsSection(String name, DexFile file) {
        super(name, file, 4);
    }

    /** {@inheritDoc} */
    @Override
        protected void orderItems() {
            int idx = 0;

            if (items().size() > DexFormat.MAX_MEMBER_IDX + 1) {
                throw new DexIndexOverflowException(getTooManyMembersMessage());
            }

            for (Object i : items()) {
                ((MemberIdItem) i).setIndex(idx);
                idx++;
            }
        }

    private String getTooManyMembersMessage() {
        Map<String, AtomicInteger> membersByPackage = new TreeMap<String, AtomicInteger>();
        for (Object member : items()) {
            String packageName = ((MemberIdItem) member).getDefiningClass().getPackageName();
            AtomicInteger count = membersByPackage.get(packageName);
            if (count == null) {
                count = new AtomicInteger();
                membersByPackage.put(packageName, count);
            }
            count.incrementAndGet();
        }

        Formatter formatter = new Formatter();
        try {
            String memberType = this instanceof MethodIdsSection ? "method" : "field";
            formatter.format("Too many %s references: %d; max is %d.%n" +
                    Main.getTooManyIdsErrorMessage() + "%n" +
                    "References by package:",
                    memberType, items().size(), DexFormat.MAX_MEMBER_IDX + 1);
            for (Map.Entry<String, AtomicInteger> entry : membersByPackage.entrySet()) {
                formatter.format("%n%6d %s", entry.getValue().get(), entry.getKey());
            }
            return formatter.toString();
        } finally {
            formatter.close();
        }
    }

}

// 如果方法数大于0xffff就提示65k错误
if (items().size() > DexFormat.MAX_MEMBER_IDX + 1) {
    throw new DexIndexOverflowException(getTooManyMembersMessage());
}

// 这个DexFormat.MAX_MEMBER_IDX就是0xFFFF
/**
 * Maximum addressable field or method index.
 * The largest addressable member is 0xffff, in the "instruction formats" spec as field@CCCC or
 * meth@CCCC.
 */
public static final int MAX_MEMBER_IDX = 0xFFFF;