Why Decompiled Java Code Is Sometimes Wrong

Decompiled Java source is an approximation — not a copy. This article explains why decompilers produce incorrect, uncompilable, or misleading output, and when to trust it.

Compilation Is a One-Way Trip

Lost Variable Names

Synthetic Methods and Bridge Methods

Compiler Optimizations That Change Shape

Type Erasure and Generics

Lambdas and Method References

Obfuscation Amplifies All of the Above

When to Trust Decompiled Output

Decompiler vs. Disassembler